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three_jeeps <jjhudak@gmail.com>: Apr 29 10:28AM -0700 > What you really need is a Fein cutter with an L shaped blade. (they are normally used to cut windshields out of cars)   > Anyway, thanks in advance for anything useful on this matter. It makes a big difference in the value of the unit.   >Have you tried boosting the filament voltage ? For one it is the best way to extend the life of a CRT, rather than rejuvinating. I wouldn't recommend that for a CRT unless it was in a TV, the color CRTs pull quite a bit of current and guess where it all comes from - the cathodes.   A common trick to boost filament voltage as well as grid voltage was through the use of aftermarket transformer 'CRT boosters'...Basically a dongel that was inserted between the crt socket and the crt pins. Been so long, I forget how they were sized, and am sure you would be hard pressed to find one nowadays...

John Robertson <spam@flippers.com>: Apr 29 10:50AM -0700 On 2019/04/29 10:28 a.m., three_jeeps wrote:   >> Anyway, thanks in advance for anything useful on this matter. It makes a big difference in the value of the unit.   >> Have you tried boosting the filament voltage ? For one it is the best way to extend the life of a CRT, rather than rejuvinating. I wouldn't recommend that for a CRT unless it was in a TV, the color CRTs pull quite a bit of current and guess where it all comes from - the cathodes.   > A common trick to boost filament voltage as well as grid voltage was through the use of aftermarket transformer 'CRT boosters'...Basically a dongel that was inserted between the crt socket and the crt pins. Been so long, I forget how they were sized, and am sure you would be hard pressed to find one nowadays...   These were a simple step-up auto-transformer designed for 50/60Hz. I have one or two lying around my shop and any old radio/TV museum would have a pile of them I'm sure.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Fox's Mercantile <jdangus@att.net>: Apr 29 01:01PM -0500 On 4/29/19 12:50 PM, John Robertson wrote:   > These were a simple step-up auto-transformer designed for 50/60Hz. I > have one or two lying around my shop and any old radio/TV museum would > have a pile of them I'm sure.   That's all well and good, but those had one of 4-5 common TV picture tube plug/socket pairs. I seriously doubt you could find one with the matching connectors for a bastard CRT.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

three_jeeps <jjhudak@gmail.com>: Apr 29 11:48AM -0700 >That's all well and good, but those had one of 4-5 common TV picture tube plug/socket pairs. I seriously doubt you could find one with the matching connectors for a bastard CRT.   I just looked on E-bay - a number of crt boosters are available. One would have to compare pinouts/sockets (for location & form factor) to see if they match. In the event they didn't match, one could break apart the sockets to expose the crimped wires and then individually mate them to the pins on the crt (and the original socket as well). It would save a little time as compared to rolling your own.

tabbypurr@gmail.com: Apr 30 03:54AM -0700 On Monday, 29 April 2019 19:48:36 UTC+1, three_jeeps wrote: > matching connectors for a bastard CRT.   > I just looked on E-bay - a number of crt boosters are available. One would have to compare pinouts/sockets (for location & form factor) to see if they match. In the event they didn't match, one could break apart the sockets to expose the crimped wires and then individually mate them to the pins on the crt (and the original socket as well). > It would save a little time as compared to rolling your own.   With most TVs it's easier to put an extra turn on the LOPTF     NT

"J.B. Wood" <arl_123234@hotmail.com>: Apr 29 01:05PM -0400 Hello, and my apologies for not a repair query but since this ng seems well attended -   In the old days of copper-wire analog phone service, on Western-Electric (Ma Bell) residential phone installations, the twisted-two wire outside plant phone line first encountered a terminal block (usually in the basement/laundry room or garage) inside the house. All the phone extensions in the home were connected to that block which also provided a third terminal with a wire that was earthed (run to a clamp on a metallic water pipe). The yellow wires from the phone extensions were connected to the earthed terminal. The black wires from the phone extensions if not used were usually just clipped short or coiled around the gray outer jacket of the 4-wire line. Does anyone know if this terminal block provided an internal lightning arrestor of some sort? Thanks for your time and comment. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com

Fox's Mercantile <jdangus@att.net>: Apr 29 12:18PM -0500 On 4/29/19 12:05 PM, J.B. Wood wrote: > Does anyone know if this terminal block provided an internal lightning > arrestor of some sort?   You're thinking of one of these: <https://i.ebayimg.com/images/g/sssAAOSwkB5b9gwV/s-l1600.jpg>   And yes, the arresters are under the two hex caps. A pair of carbon rectangles that would fail short and protect the inside wiring.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

John Robertson <spam@flippers.com>: Apr 29 10:38AM -0700 On 2019/04/29 10:18 a.m., Fox's Mercantile wrote:   > And yes, the arresters are under the two hex caps. > A pair of carbon rectangles that would fail short and protect > the inside wiring.   Or this (second picture down):   https://the-electric-orphanage.com/wp-protection-equipment-for-open-wire/   I saw something like that in my grandmother's house back in the 60s...   John ;-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"J.B. Wood" <arl_123234@hotmail.com>: Apr 29 01:48PM -0400 On 4/29/19 1:18 PM, Fox's Mercantile wrote:   > And yes, the arresters are under the two hex caps. > A pair of carbon rectangles that would fail short and protect > the inside wiring.   ello, and thanks for the quick reply. Yep, that's precisely what I remember. Sincerely,   -- J. B. Wood e-mail: arl_123234@hotmail.com

Fox's Mercantile <jdangus@att.net>: Apr 29 12:58PM -0500 On 4/29/19 12:38 PM, John Robertson wrote: > Or this (second picture down):   > https://the-electric-orphanage.com/wp-protection-equipment-for-open-wire/   > I saw something like that in my grandmother's house back in the 60s...   *laughs* I have one of those at the shop, it was the original protector. My shop was built in 1919.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

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N_Cook <diverse@tcp.co.uk>: Apr 29 04:19PM +0100 A much better solution , I picked up some surplus new of these "gigabyte 12CF1-1id133-61r" computer cables. .025 inch spacing cable for 0.1 inch headers , as inter-line ground wires and extra bridging IDC prongs inside the headers. Anyway ribbon is 0.635mm spacing with proper copper conductors (so heavy to the handling) , so its quite easy to strip off the insulation, at an end, after unclamping an IDC. Solder a 5 way strip at a time , as not 0.5mm spacing and add lacquer insulation afterwards.

jurb6006@gmail.com: Apr 28 12:03PM -0700 Thanks, it might help. However the tube socket is wired to a set of wires that do down to a socket on the board. There is no way to tell for sure the connections aren't changed from what you would get straight at the base of the tube. I haven't found a decent page on the CRT in the manual, in fact it says something like "provisional" as if they weren't quite sure whose tubes they going to use.   Having the pinout, even in low resolution is better than nothing.

jurb6006@gmail.com: Apr 28 12:12PM -0700 >"I've been dealing with a slightly similar problem myself... I bought a CTS service monitor whose scope is working-but-dim. Fortunately it has a 3RP CRT (like the Cushman and Macintosh systems do) and I have a local source for a used tube (and there are online sources as well). "   Have you tried boosting the filament voltage ? For one it is the best way to extend the life of a CRT, rather than rejuvinating. I wouldn't recommend that for a CRT unless it was in a TV, the color CRTs pull quite a bit of current and guess where it all comes from - the cathodes.   But scope cathodes don't get loaded heavily. they can be just as bright as a tube pulling 20 times more current easily because they are not generating a raster.   If it turns out to be weak emission in this tube I am not exactly sure how to boost the filament voltage. It seems to run off a resistive divider, but for a small tube which is a RAY type tube not a raster type it is sufficient. But then doing anything in that circuit might do something to the G1 bias or whatever.   Thing is also figuring out how to actually test the thing if/when all the other possibilities are eliminated...

jurb6006@gmail.com: Apr 28 12:16PM -0700 >"shango66 on youtube does some good explanations re CRT emission problem fixing. Though I don't remember him discussing EHT boosting. "   I'll have to look into that. Nobody in their right mind would try to save an old CRT by boosting the main accelerating voltage.   First I will try the grid bias, if that does it fine, that is IF that is the problem and it isn't some other fault.   Thing is I just heard from the customer that he scope used to work, he actually found the burning -500 rectifier. There are no shorts currently, the new rectifier is doing fine in there.   But no trace.

jurb6006@gmail.com: Apr 28 12:45PM -0700 >"** Monochrome CRTs and monitors operated with HT voltages in the range of 16 to 20kV and were made with plain glass while colour CRTs operated at voltages about 5 or 6kV higher and were made with thick leaded glass at the face."   >"The reason was X-ray generation."   I believe that for whatever reason they started using barium for that. That was from a CRT rebuilder. We had, after the tube days, a new rating on CRTS, bars. On the bell of the tube there were either one, two or three bars right in the glass. the three bars were the only ones we could legally use in most of the newer delta gun sets. The older ones would work but well, we use the three bar tubes when called for. When they got to inline guns, even the original GE ones, (Sony was still first) they all has three bar glass.   If I remember correctly the three bar tubes were good up to 35KV.   >"However, seeing small kids sitting less than a metre from colour CRT screens always made me cringe."   Kids here more like ½ metre. I wonder what the physiological effects could have been. Well, it seems more people in my age group wear glasses but can we attribute that to that ? Not so sure.   I remember them saying that Xrays dropped due to gravity, though I kinda doubt it. Maybe as much as any photon would but there is no evidence I can't find now that it is any more than that miniscule drop. But they sold people on floor model TVs with it.   Actually thing about it is I would rather have a TV at or below eye level. In fact people have their monitors set at an upward angle which reflects more ambient light. I avoid that but have found that some edge lit LCD screens like in laptops simply are not designed for that.   Needless to say, this Xray shit is a hijack because this thing only has 500 volts. You get real Xrays out of that voltage maybe I will kiss your ass on public square and give you ½ an hour to draw a crowd. (no beans and no mooning)

tabbypurr@gmail.com: Apr 28 02:19PM -0700 On Sunday, 28 April 2019 20:16:35 UTC+1, jurb...@gmail.com wrote: NT:   > >"shango66 on youtube does some good explanations re CRT emission problem fixing. Though I don't remember him discussing EHT boosting. "   > I'll have to look into that. Nobody in their right mind would try to save an old CRT by boosting the main accelerating voltage.   Well I've done it when all else failed, and it would not result in excessive x-ray emission. I kept one such set for 10 years or so, it kept going just fine. Why do you dislike it?     NT

jurb6006@gmail.com: Apr 28 08:03PM -0700 >"Well I've done it when all else failed, and it would not result in excessive x-ray emission. I kept one such set for 10 years or so, it kept going just fine. Why do you dislike it? "   Well you got lucky. High voltage components are particularly prone to failure even at their rated voltage and you may not have had problems, but I bet out of 10 times at least 7 would be a problem.   Another thing is what did you do about deflection sensitivity ?   How do you know it did not result in excessive Xray emission ? Piece of plywood and some photographic film in a dark room ?

tabbypurr@gmail.com: Apr 29 04:57AM -0700 On Monday, 29 April 2019 04:03:25 UTC+1, jurb...@gmail.com wrote: NT:   > >"Well I've done it when all else failed, and it would not result in excessive x-ray emission. I kept one such set for 10 years or so, it kept going just fine. Why do you dislike it? "   > Well you got lucky. High voltage components are particularly prone to failure even at their rated voltage and you may not have had problems, but I bet out of 10 times at least 7 would be a problem.   There is a small failure rate at the original voltage. TV parts are generally run well below parts mfrs' rated voltage to improve reliability, eg 25kV on a 40kV part, 15kV on a 25kV part. Failure rate climbs as you apply more, but it only takes a small boost, 5-10%, and the increase in failures is not great for that much. But yes it's there. However the key phrase is when all else fails. 90% beats 0% by a long way.   Cleaning the EHT stuff always helps, dirt degrades insulation capability..   > Another thing is what did you do about deflection sensitivity ?   Raise B+ the same amount. In TVs the easiest way is just to raise B+ across the board.   > How do you know it did not result in excessive Xray emission ? Piece of plywood and some photographic film in a dark room ?   The OP has a 500v tube. Otherwise look up the datasheet for the CRT, they're often run below rated v.   You can also use a counter. It can't measure all the tube's output, but it can measure background, and relative original & boosted outputs. Then you know what %age the increase is and can see if that's within requirements.     NT

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John-Del <ohger1s@gmail.com>: Apr 27 09:53AM -0700 On Saturday, April 27, 2019 at 1:46:37 AM UTC-4, John Robertson wrote: > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."   You triggered an old (dormant) memory. Back in the 1970s, certain GE portable TVs had a recall campaign because of excessive X-Ray emissions. GE opted to replace the glass HV rectifier with a leaded rubber jacket tube instead of building a new HV cage to retrofit the chassis. Swapping the lead coated rectifier tube took 3 minutes, and 2:50 of that was pulling off the plastic rear cover and reinstalling. I'm pretty sure I still have one of those leaded rectifier tubes somewhere.

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jurb6006@gmail.com: Apr 26 10:22AM -0700 Does anyone know anything about these ? I know the basics but there are details missing from the print, LIKE THE PINOUT of the CRT !   I can see though (thank you Drs Budrous and Stewart) so I can see the thicker wires, those are pretty much at cathode potential, -500 volts. I can also find the deflection plates and with the centering make the DC voltages equal, still no display.   Unless there's something I missed I need to get into the grid and focus voltages and if those are all there, the CRT is bad ?   From what I hear you would need a SWAT team and a bunch of automatic weapons to get a replacement CRT. Even people with experience on these things, how many receivers had built in scopes ? I saw one in another brand once but can't remember what it was, maybe a Kenwood ? Other than that only Marantz and then even very few models.   I got the other problems fixed, it had a fault on the one power amp board and a bad transistor on the tone amp board which is by the way stuck to the chassis with double sided foam tape ! For what they charged fro these things, foam tape ? And you should see the PITA it is to remove, I was thinking "This board it gonna break", but it didn't.   What you really need is a Fein cutter with an L shaped blade. (they are normally used to cut windshields out of cars)   Anyway, thanks in advance for anything useful on this matter. It makes a big difference in the value of the unit.

JC <Chipbee40_SpamNo@yahoo.com>: Apr 26 02:06PM -0400 > I got the other problems fixed, it had a fault on the one power amp board and a bad transistor on the tone amp board which is by the way stuck to the chassis with double sided foam tape ! For what they charged fro these things, foam tape ? And you should see the PITA it is to remove, I was thinking "This board it gonna break", but it didn't.   > What you really need is a Fein cutter with an L shaped blade. (they are normally used to cut windshields out of cars)   > Anyway, thanks in advance for anything useful on this matter. It makes a big difference in the value of the unit.   Pinouts here :   https://www.radiomuseum.org/tubes/tube_g3-11gj.html   replacement here (bit spendy) :   Ebay item no 254200412600

dplatt@coop.radagast.org (Dave Platt): Apr 26 02:45PM -0700 In article <65b4af8a-0653-49c7-b9ea-5599fd271ffd@googlegroups.com>, >Does anyone know anything about these ? I know the basics but there are details missing from the print, >LIKE THE PINOUT of the CRT !   The service manual is available at HiFiEngine.com (free registration required to download). The scope-module schematic is on page 62 of the original and the tube ponout is given.   The scope V901 is "CRT with 13-pin Nixie base", Marantz part number 337-1000. According to one article I read elsewhere, it's originally a Siemens D3-II GJ.   After all of these years, I wouldn't be surprised if the cathode were worn out (low emission) or the CRT has become gassy.   >From what I hear you would need a SWAT team and a bunch of automatic weapons to get a replacement CRT.   From what I read, it's well beyond that now... you'd need the services of at least four demigods, and several falling asteroids to blast one loose. They're probably mostly in the hands of owners of Marantz receivers in that series, being preserved against a Time Of Need.   >Even people with experience on these things, how many receivers had built in scopes ? I saw one in another >brand once but can't remember what it was, maybe a Kenwood ? Other than that only Marantz and then even >very few models.   Some Macintosh tuners had scopes. Mac seems to have used a more common/popular tube variety (a 3RP series), for which there are still some used-but-good tubes available and even a few Chinese-build clones.   >Anyway, thanks in advance for anything useful on this matter. It makes a big difference in the value of the unit.   One guy who wrote, said that he'd sold a Model 19, and had also sold a new-old-stock replacement CRT he had for it. He got more for the CRT than for the receiver.   I've been dealing with a slightly similar problem myself... I bought a CTS service monitor whose scope is working-but-dim. Fortunately it has a 3RP CRT (like the Cushman and Macintosh systems do) and I have a local source for a used tube (and there are online sources as well).   I was thinking of trying to cons up a solid-state replacement. I think one could probably be made by using a Raspberry Pi or similar processor as a core, hooked to a reasonably fast (audio-speed) two-channel SPI-based ADC which would sample the horizontal and vertical deflection voltages (suitably attenuated and centered of course). The Pi would capture the data, and then draw it to a 2" color LCD.

tabbypurr@gmail.com: Apr 26 04:32PM -0700 On Friday, 26 April 2019 22:45:21 UTC+1, Dave Platt wrote: > vertical deflection voltages (suitably attenuated and centered of > course). The Pi would capture the data, and then draw it to a 2" > color LCD.   shango66 on youtube does some good explanations re CRT emission problem fixing. Though I don't remember him discussing EHT boosting.     NT

John Robertson <spam@flippers.com>: Apr 26 05:48PM -0700 >> color LCD.   > shango66 on youtube does some good explanations re CRT emission problem fixing. Though I don't remember him discussing EHT boosting.   > NT   Aren't you going to run the risk of X-Ray production if the EHT is increased beyond a reasonable point? The link below says 5KV and up can produce X-Rays:   https://www.nde-ed.org/EducationResources/HighSchool/Radiography/xraygenerators.htm   We have a problem in my industry with 13" colour tubes being over driven by ignorant people using the wrong HV transformer (from 19" monitors) and getting the tube into the soft X-ray range...   John :-#(#

Trevor Wilson <trevor@rageaudio.com.au>: Apr 27 11:59AM +1000 On 27/04/2019 10:48 am, John Robertson wrote: > by ignorant people using the wrong HV transformer (from 19" monitors) > and getting the tube into the soft X-ray range...   > John :-#(#   **I've had the odd X-ray and, being an inquisitive chap, I usually examine the equipment as best as I am able. I've never found an X-ray machine that operates below 75kV. I recall reading some years ago that X-rays begin to be a problem at around 20kV. That said, I would imagine a small tube like the one fitted to the Model 19 (which I also own, BTW) would operate on a potential of around -500 Volts or so. WAY lower than 5kV.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

John Robertson <spam@flippers.com>: Apr 26 10:46PM -0700 On 2019/04/26 6:59 p.m., Trevor Wilson wrote: > a small tube like the one fitted to the Model 19 (which I also own, BTW) > would operate on a potential of around -500 Volts or so. WAY lower than > 5kV.   I wish you were right about 75KV being the minimum voltage to generate X-rays, but the article suggested otherwise. I'd agree that anything under 1000V is likely to do anything other than shock you - I've found nothing so far to challenge that assumption.   The problem with video game repairs with using a 19" flyback on a 13" tube is the tube is then working at upwards of 25KV, which the specs on the tube say is dangerous. The maximum safe voltage for these 13" tubes was around 20KV.   An interesting paper on 6BK4 tubes being driven (60KV) to give off X-Rays, but it appears they would also generate X-Rays at voltages found in colour TVs:   http://www.belljar.net/xray.htm   Later 6KB4 tubes had leaded glass it seems.   Well, that is enough time spent on X-Ray production for now. sure looks like under 1KV is quite safe, and over 20KV it gets interesting.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

pallison49@gmail.com: Apr 26 11:02PM -0700 John Robertson wrote:   > Later 6KB4 tubes had leaded glass it seems.   > Well, that is enough time spent on X-Ray production for now. sure looks > like under 1KV is quite safe, and over 20KV it gets interesting.   ** Monochrome CRTs and monitors operated with HT voltages in the range of 16 to 20kV and were made with plain glass while colour CRTs operated at voltages about 5 or 6kV higher and were made with thick leaded glass at the face.   The reason was X-ray generation.   However, seeing small kids sitting less than a metre from colour CRT screens always made me cringe.       .... Phil

Lucifer <LuciferMorningstar@bigpond.com>: Apr 27 05:01PM +1000 On Sat, 27 Apr 2019 11:59:49 +1000, Trevor Wilson >a small tube like the one fitted to the Model 19 (which I also own, BTW) >would operate on a potential of around -500 Volts or so. WAY lower than >5kV.   I had an HF modem with a built in scope for tuning. I still have a 20" colour TV with a CRT, and a 5" colour portable TV with a CRT.

Trevor Wilson <trevor@rageaudio.com.au>: Apr 27 07:35PM +1000 On 27/04/2019 3:46 pm, John Robertson wrote: >> lower than 5kV.   > I wish you were right about 75KV being the minimum voltage to generate > X-rays,   **Read what I wrote. Particularly this point:   "I recall reading some years ago that X-rays begin to be a problem at around 20kV."     but the article suggested otherwise. I'd agree that anything > under 1000V is likely to do anything other than shock you - I've found > nothing so far to challenge that assumption.   **I've never heard of any issues surrounding X-ray production at potentials as low as 5kV. And at the several hundred Volts on a Model 19 tube, there is zero chance of a problem.   > tube is the tube is then working at upwards of 25KV, which the specs on > the tube say is dangerous. The maximum safe voltage for these 13" tubes > was around 20KV.   **Sure. Colour picture tubes are a known source of X-rays.     > Later 6KB4 tubes had leaded glass it seems.   > Well, that is enough time spent on X-Ray production for now. sure looks > like under 1KV is quite safe, and over 20KV it gets interesting.   **Which is pretty much what I said.     -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

tabbypurr@gmail.com: Apr 27 05:38AM -0700 On Saturday, 27 April 2019 01:48:25 UTC+1, John Robertson wrote: > by ignorant people using the wrong HV transformer (from 19" monitors) > and getting the tube into the soft X-ray range...   > John :-#(#   I guess it's largely been answered :) Depends what voltage you're running at, how much boost & how much leeway you have with xray production. I would not consider EHT boosting until other options were exhausted. A 500v tube is not an issue though.   Medical x-rays use much higher voltages so the rays are harder, ie penetrate more.     NT

Chuck <ch@dejanews.net>: Apr 26 11:51AM -0500 On Thu, 25 Apr 2019 11:09:09 -0700, Bill Martin <wwm@wwmartin.net> wrote:     >Where does the model 2230 fall in this lineup? I still have one of >those, bought in about 1970, I think...still worked last time I powered >it on...several years ago.   It is a pretty decent receiver. It wasn't made by Marantz in the U.S.. It was manufactured by Standard Radio in Japan.

jurb6006@gmail.com: Apr 26 10:05AM -0700 >"**The 2230 is old school Marantz. Very nicely laid out, easy to service and TO3 output devices. Should last a very, very long time. The smaller receivers of the time used plastic pack output devices and were significantly less reliable than those (like the 2230) that employed TO3 output devices. "   Just don't break the dial string. You said way back you had trouble with cassette decks ? Well I got one trouble and that is dial stringing. I wish there was a guy around I could just pay to do it.

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 26 11:00AM -0700 > Just don't break the dial string. You said way back you had trouble with cassette decks ? Well I got one trouble and that is dial stringing. I wish there was a guy around I could just pay to do it.     Invest in a couple of small hemostats, some curved suture needles (coarse) and a couple of dental picks. Buy a box of small springs from McMaster-Carr, and you will find your life to be much easier. That, and some Dacron fishing line of the correct gauge (does not stretch and holds very tight knots very well) - simple.   Peter Wieck Melrose Park, PA

John-Del <ohger1s@gmail.com>: Apr 26 11:40AM -0700 > >"**The 2230 is old school Marantz. Very nicely laid out, easy to service and TO3 output devices. Should last a very, very long time. The smaller receivers of the time used plastic pack output devices and were significantly less reliable than those (like the 2230) that employed TO3 output devices. "   > Just don't break the dial string. You said way back you had trouble with cassette decks ? Well I got one trouble and that is dial stringing. I wish there was a guy around I could just pay to do it.     My dad hated dial cord stringing. When he got married in the 1940s and opened up a radio repair shop, he had my mom string up radios which she did with no trouble at all. She could also knit, sew, crochet, and make ravioli so good that you would cry.   I just restrung one of those "Crosley" radio/phono/cd abominations and it looks like it was designed wrong. One of the pulleys was on the far side of the main tuner pulley and very close to it. There was no way that would have worked easily with the dial cord pulled over the top of the main pulley in the opposite direction. It didn't even function as a back tension pulley to keep the lateral pull on the tuner even. I shortened the dial cord leaving the odd pulley out and it worked easily and smoothly and in the correct direction with only two turns on the tuning shaft.

Trevor Wilson <trevor@rageaudio.com.au>: Apr 27 06:47AM +1000 >> "**The 2230 is old school Marantz. Very nicely laid out, easy to service and TO3 output devices. Should last a very, very long time. The smaller receivers of the time used plastic pack output devices and were significantly less reliable than those (like the 2230) that employed TO3 output devices."   > Just don't break the dial string. You said way back you had trouble with cassette decks ? Well I got one trouble and that is dial stringing. I wish there was a guy around I could just pay to do it.   **I broke a few in the early days. Once bitten, twice shy. I haven't damaged one since. PITA to repair.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"malua mada!" <fritzo2ster@gmail.com>: Apr 26 12:34PM -0700 The COM port is for a remote display or to stack another unit for increased punch. Get a car battery and jumper cables, connect DC. Expect a spark. If the unit is silent find a on/off pushbutton switch . If it ticks it is in search mode. If it hums it is ON. Good luck

Jeff Liebermann <jeffl@cruzio.com>: Apr 26 10:41AM -0700 On Thu, 25 Apr 2019 11:39:06 -0500, Sem Jansen >of those college textbooks are even close to the practical use hands on >SAMS and Forest Mims type which we all used to read a few decades ago for >all our hardware designs.   Are you looking for a book on designing analog integrated circuits, or a book on using analog integrated circuits in some kind of device? Forrest Mims III wrote mostly about circuit design, not integrated circuit design.   >Do you know of a hands on technician type of analog ic design book?   Only one book? It would be difficult to cram all things analog into one book. Art of Electronics III is the best I can suggest for everything under one cover. <https://artofelectronics.net> Be wary of counterfeit copies.   Also see books by Jim Williams and Bob Dobkin: <https://www.amazon.com/Analog-Circuit-Design-Applications-Solutions/dp/0123851858/> <https://www.amazon.com/Analog-Circuit-Design-Immersion-Black/dp/0123978882/> <https://www.amazon.com/Analog-Circuit-Design-Three-Collection/dp/0128000015/>   Also, you might consider asking the same question in sci.electronics.design.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

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Sem Jansen <JansenSem999999@caiway.net>: Apr 25 11:39AM -0500 I am thinking about learning how to do analog ic design at home.   I don't know what low cost software yet exists out there so this is an early question about how to learn more about how analog ic chips are designed.   I went to the local college book store and bought a few electrical engineering textbooks on cmos ic design which I am reading and where I get the concept of plls, classes of amplifiers, bandpass filters, etc but none of those college textbooks are even close to the practical use hands on SAMS and Forest Mims type which we all used to read a few decades ago for all our hardware designs.   Do you know of a hands on technician type of analog ic design book?

Sem Jansen <JansenSem999999@caiway.net>: Apr 25 11:40AM -0500 I am thinking about learning how to do analog ic design at home.   I don't know what low cost software yet exists out there so this is an early question about how to learn more about how analog ic chips are designed.   I went to the local college book store and bought a few electrical engineering textbooks on cmos ic design which I am reading and where I get the concept of plls, classes of amplifiers, bandpass filters, etc but none of those college textbooks are even close to the practical use hands on SAMS and Forest Mims type which we all used to read a few decades ago for all our hardware designs.   Do you know of a hands on technician type of analog ic design book?

John Robertson <spam@flippers.com>: Apr 25 09:57AM -0700 On 2019/04/25 9:39 a.m., Sem Jansen wrote: > SAMS and Forest Mims type which we all used to read a few decades ago for > all our hardware designs.   > Do you know of a hands on technician type of analog ic design book?   Rummage around http://www.archive.org or http://www.bitsavers.com both have lots of archived manuals...   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Jon Elson <elson@pico-systems.com>: Apr 25 12:39PM -0500 Sem Jansen wrote:   > SAMS and Forest Mims type which we all used to read a few decades ago for > all our hardware designs.   > Do you know of a hands on technician type of analog ic design book? Well, the problem with this is you need IC design software. There is a little bit of open-source software, mostly dating to the 1980's. Otherwise, you are stuck with Cadence, starting at $50K per seat, with options can run something like $250 K per YEAR.   Then, if you just want to play around with design and simulation, that can be done, but otherwise you will need serious money to fab chips. MOSIS can get you into a multi-project wafer for about $10 - 15K for a small design, but you will have to jump through amazing hoops to get the fabs NDAs signed to their satisfaction. Last time our group did this, it took SIX MONTHS to get the legal documents worked out! And, you will HAVE to be running Cadence, I think most of the fab's design kits are now for Cadence only. Mentor still exests, but I think most designers have moved away from them.   Jon

Sem Jansen <JansenSem999999@caiway.net>: Apr 25 01:04PM -0500 said:   > Well, the problem with this is you need IC design software. There is a > little bit of open-source software, mostly dating to the 1980's.   You are correct that the open source kind of software, with a book that goes with it is what I'm looking for, since I'm familiar with Composer schematic capture and HSpice simulation, and Virtuoso layout, all from the Edge and Opus days and then, more recently, Caliber for DRC & LVS.   What I want, really, is just what anyone at home would want I would think which is to have free analog design schematic capture software which just does schematics and spice and then does basic layout of something no larger than about 300 devices and then a quick basic drc and lvs if that also exists.   I'm not going to actually put the GDSII on a shuttle - I just want to do it for the fun and education and experience of designing a working small cmos PLL or OpAmp or something of that small size.   I could write the book if it doesn't exist, so the software is mostly what I need, I guess, if the book with software doesn't exist.   If the software is open source, then I could even include it maybe in a cdrom with the book if I write it.   It's not hard to design an analog ic of a small size if you have those tools but they cost too much for a home user.   I hadn't thought about the pdk problem until you mentioned it where MOSIS might be the right way to go if they'll let me use it for free.   I wonder if MOSIS would want me to write a book for them for home users?

Jon Elson <elson@pico-systems.com>: Apr 25 01:56PM -0500 On Thu, 25 Apr 2019 13:04:10 -0500, Sem Jansen wrote:       > I'm not going to actually put the GDSII on a shuttle - I just want to do > it for the fun and education and experience of designing a working small > cmos PLL or OpAmp or something of that small size.   Years ago, when I was getting into this to work with a MUCH more experienced guy who was actually going to be doing the IC design, and I was going to be doing the overall systems design, was to load Mentor through our university license, and work through a small tutorial. I think I built a 2-input CMOS gate in schematic, then implemented the several transistors and simulated it. It took me a couple days to get that far. But, once I had done that, I was a lot more able to understand the other guy's language.   > tools but they cost too much for a home user.   > I hadn't thought about the pdk problem until you mentioned it where > MOSIS might be the right way to go if they'll let me use it for free.   If you are at a university, I think you could do this at no cost, through their university education program. Otherwise, I'm pretty sure NO WAY! > I wonder if MOSIS would want me to write a book for them for home users?   NO! "Home users" just does not make any sense. MOSIS was set up to do two things. One, get special-purpose ICs fabricated at reasonable cost, and also to offer students the opportunity to have a thesis design fabricated so they could see where they goofed. MOSIS was originally funded largely by the Defense Department's DARPA program, but has largely been downgraded to have to scratch for $ to keep open.   We get a few more chips made than the minimum, our chips are not really all that small, we use old, much cheaper processes, and our chip batch typically runs about $40K. Also, it typically now takes about six months to get our chips back from the fab. I just don't see why MOSIS would have any interest in people who can't afford to actually have the chips fabbed.   Jon

Chris Jones <lugnut808@spam.yahoo.com>: Apr 26 10:31AM +1000 On 26/04/2019 02:40, Sem Jansen wrote: > SAMS and Forest Mims type which we all used to read a few decades ago for > all our hardware designs.   > Do you know of a hands on technician type of analog ic design book?   There is quite a good book by Hans Camenzind, designer of the 555 timer. It is free and available for download: http://www.designinganalogchips.com/   Also there are some people starting to make chips at home these days: http://sam.zeloof.xyz/first-ic/ Maybe he will even fabricate your design!

C_Mechanic@f117.n2.z21.fsxnet (C_Mechanic): Apr 25 09:40PM +1200 * * On Thursday 25 Apr 2019 115 at 11:40 AM, * Sem Jansen said to All, * about SAMs or Forest Mims style analog ic design book ... *   You might try mouser.com, they handle lots of analog devices :) and might have a book or two ...     .- Keep the faith, --------------------------------------------------. | | | Ben aka cMech Web: http|ftp|binkp|telnet|ssh://cmech.dynip.com | | | | vvvvvv Email: fido4cmechSPAM(at)lusfiberBLOCK.net | | { O O } Home page: http://cmech.dynip.com/homepage/ | | __m___oo___m__ | `--| | | |-- -------------------------------------------------'   ... If you see a snake, just kill it. Don't appoint a committee on snakes.

bitrex <user@example.net>: Apr 26 03:12AM -0400 On 4/25/19 12:40 PM, Sem Jansen wrote: > SAMS and Forest Mims type which we all used to read a few decades ago for > all our hardware designs.   > Do you know of a hands on technician type of analog ic design book?   <http://www.designinganalogchips.com/>

ggherold@gmail.com: Apr 26 07:50AM -0700 On Thursday, April 25, 2019 at 12:39:26 PM UTC-4, Sem Jansen wrote: > SAMS and Forest Mims type which we all used to read a few decades ago for > all our hardware designs.   > Do you know of a hands on technician type of analog ic design book?   Do you have the Art of Electronics? There is 'Analysis and Design of Analog Integrated Circuits', by Gray and Meyer, but I would not call it 'hands on'. https://www.amazon.com/Analysis-Design-Analog-Integrated-Circuits/dp/0470245999   You can find the earlier editions for much less money. I have the 3rd ed.   George H.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Apr 26 11:44AM -0400 > https://www.amazon.com/Analysis-Design-Analog-Integrated-Circuits/dp/0470245999   > You can find the earlier editions for much less money. I have the 3rd ed.   > George H.   Toumazou's book "Analog IC design: The current-mode approach" is an excellent read.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net https://hobbs-eo.com

Bill Martin <wwm@wwmartin.net>: Apr 25 11:09AM -0700 On 4/19/19 3:23 AM, Trevor Wilson wrote: > beautiful backlit dials. It was so sad. Marantz was then (partly) sold > to Philips. Philips actually improved things considerably and the SR > series was consigned to the dustbin of history.   Where does the model 2230 fall in this lineup? I still have one of those, bought in about 1970, I think...still worked last time I powered it on...several years ago.

jurb6006@gmail.com: Apr 25 12:31PM -0700 Let me set this to rest. That IC has + and - inputs. Treat it like an OP AMP.   Know how to troubleshoot an OP AMP ? this is the same thing only bigger. It also might have booststrap caps and maybe some bypass, but even without them it should kinda work.

Trevor Wilson <trevor@rageaudio.com.au>: Apr 26 07:18AM +1000 On 26/04/2019 4:09 am, Bill Martin wrote:   > Where does the model 2230 fall in this lineup? I still have one of > those, bought in about 1970, I think...still worked last time I powered > it on...several years ago.   **The 2230 is old school Marantz. Very nicely laid out, easy to service and TO3 output devices. Should last a very, very long time. The smaller receivers of the time used plastic pack output devices and were significantly less reliable than those (like the 2230) that employed TO3 output devices.   -- Trevor Wilson www.rageaudio.com.au   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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