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oldschool@tubes.com: Apr 05 01:02PM -0400 It seems the most "famous" germanium diode was the 1N34(A). Heck, I remember that number from way back....   I googled up a data sheet for ALL germanium diodes. (Assuming they are all listed), it seems there are about 20 of them.   The 1N60 is another common one, along with 1N270.   Anyhow, my reason for an interest in them is because I'm making up some RF probes for my old oscilloscope and other test gear. These probes are very simple, a cap, resistor and a diode. Making up a suitable housing is more troublesome than the electronics within them.   I downloaded a bunch of schematics from the old Heathkits and Eico kits and others. They are all pretty much the same, except some use the 1N34 while others use the 1N60. One of these has a slightly higher PIV (I forget which one). Otherwise they dont seem too much different.   I am just wondering why some use 1N34 while others use 1N60? (and none use any of the other germanium diodes). Is there any advantage or disadvantage to either of them?   Also, why dont they use Silicon Diodes?

Chuck <chuck@mydeja.net>: Apr 05 01:17PM -0500 >use any of the other germanium diodes). Is there any advantage or >disadvantage to either of them?   >Also, why dont they use Silicon Diodes?   Because germanium diodes have a lower voltage drop and are more sensitive.   --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"pfjw@aol.com" <pfjw@aol.com>: Apr 05 11:24AM -0700 The 1N34 series is very often used in crystal radios - that should indicate the 'why' as compared to silicon diodes. It has to do with sensitivity at very low voltages.   There are silicon-based probes today, but germanium for the sensitivity is still preferred.   Peter Wieck Melrose Park, PA

oldschool@tubes.com: Apr 05 01:43PM -0400 On Wed, 5 Apr 2017 11:24:08 -0700 (PDT), "pfjw@aol.com" <pfjw@aol.com> wrote:     >There are silicon-based probes today, but germanium for the sensitivity is still preferred.   >Peter Wieck >Melrose Park, PA   OK, that makes sense....   Is there any reason to choose 1N34 versus 1N60, or will both work equally? Of the schematics I have, both were used.   I have to buy some either way, but they are cheap on ebay, like 10 of them for around $2.50 so it's no big cost. I just need to determine which one to buy. (Or the 1N270 are also quite available too).

"pfjw@aol.com" <pfjw@aol.com>: Apr 05 11:51AM -0700 > I have to buy some either way, but they are cheap on ebay, like 10 of > them for around $2.50 so it's no big cost. I just need to determine > which one to buy. (Or the 1N270 are also quite available too).   As I understand it, a 1N34(a) is a bit more rugged than a 60 and has a bit more voltage headroom before it clips (drops off) - but that in 80% of most applications, either will be fine. That is 100% second hand, and not from experience. I use the 34-series almost exclusively for this sort of thing and have at least 20 on hand at any one time, they are so cheap.   Peter Wieck Melrose Park, PA

John Robertson <spam@flippers.com>: Apr 05 11:56AM -0700 > I have to buy some either way, but they are cheap on ebay, like 10 of > them for around $2.50 so it's no big cost. I just need to determine > which one to buy. (Or the 1N270 are also quite available too).   That's why there are spec sheets - you need to figure out which one fits your application best. If it doesn't really matter then just get the convenient one.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

mike <ham789@netzero.net>: Apr 05 01:30PM -0700 > use any of the other germanium diodes). Is there any advantage or > disadvantage to either of them?   > Also, why dont they use Silicon Diodes?   1N21

Michael Black <et472@ncf.ca>: Apr 05 06:14PM -0400

oldschool@tubes.com: Apr 05 05:32PM -0400 >I went through a bunch of boards at one point, and uncovered a lot of >germanium diodes this way, certainly more than I expected.   > Michael   Thanks for the info. 1N34 is one of those numbers I never forgot. Even though I was pretty much out of electronics for near 40 years. Just like tubes, I remembered certain ones, like 6L6 6V6 5U4 6SN7 12AU7 12AX7, and the ones in the "american five" radios like 50C5 35W4 etc. So, when someone says Germanium diode, 1N34 comes to mind first....   I guess from what you said, they were used more than I thought.   I have never used a Schottky diode, but I heard of them.   If I could view that chart I downloaded (PDF) showing all the germanium diode numbers and characteristics, I'd see which of them had the higher PIV (between the 34 and the 60). But my PDF reader is broken, and will probably take a few hours to download again on dialup.... But I do think the 34 was the higher one, and if thats the case, that is what I will buy and use. I think they are a few cents cheaper too, but it's so small amount that it really dont matter.

jurb6006@gmail.com: Apr 05 04:14PM -0700 >" Schottky diodes have lower forward voltage drop than silicon, though I can't remember if it's lower than germanium. "   I think they go lower in forward drop, but I am not sure how they are with RF. They were used quite a bit in SMPSes but that doesn't mean you can just hook them up to an antenna and pick up WKRP in Cincinnati. But it does seem logical they could. I think the capacitance is an issue, an SMPS can punch though that no problem, a long wire antenna not so much.   Germanium has alot of problems, and one of them is temperature. They can only go to 100C whereas silicon can go to 200C. That is a whole different derating factor there, only half. So some silicon diodes are much better despite the voltage drop.   All this shit is only useful in very low level stuff. Nobody with half a brain would use a germanium diode or transistor in a modern design unless there was good reason. The last time I heard about it was Phase Linear, Bob Carver used germanium transistors in the current limiting circuit. I know because I had to deal with it a few years ago.   Also, there is a guy on here that wants to fix a bench power supply that uses germanium a transistor for current regulator. I would like to help but I am not quite sure what to do. There is a diode in the circuit which would have to be replaced, and then the circuit must be redesigned for the silicon transistor. I only saw a partial print of it, ad really though I can get the current limiting and whatever working, it would not be calibrated. Germanium is funny stuff. I is much different to what I am used to these days.

Allodoxaphobia <knock_yourself_out@example.net>: Apr 05 11:25PM On Wed, 5 Apr 2017 18:14:28 -0400, Michael Black wrote: > because it had been used, and diodes with that number were available > through hobby outlets. I have no idea if they were all 1N34s, but they > would have all been germanium small signal diodes.   And, then there was the 1N21 -- a germaniun diode built in a form factor to facilitate its use in microwave tubing. Handled a lot of them maontaining the MG-10 radar system on the USAF F-102 Fighter Interceptor in the 1960's.   Jonesy -- Marvin L Jones | Marvin | W3DHJ.net | linux 38.238N 104.547W | @ jonz.net | Jonesy | FreeBSD * Killfiling google & XXXXbanter.com: jonz.net/ng.htm

Ralph Mowery <rmowery28146@earthlink.net>: Apr 05 11:29PM -0400 In article <esaaecdp68ndml99tdb1d0f62naure2q1p@4ax.com>, oldschool@tubes.com says...   > I have to buy some either way, but they are cheap on ebay, like 10 of > them for around $2.50 so it's no big cost. I just need to determine > which one to buy. (Or the 1N270 are also quite available too).   Go with the 1n34A as it has about 3 times the voltage break down as the 1n60. Somewhere around 75 volts insted of 25 volts.   The germanium has a junction voltage of about .3 volts and the silicon .7 volts. Better sensitivity at low voltages.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Apr 05 11:20PM +0100 Hi,   I need to try and replace the USB chip in a rather old device.   The original chip is ISP1181BBS. I can't find this to buy, but can get ISP1181ABS.     Datasheets are here, but both appear to be pretty much identical.   A: http://pdf1.alldatasheet.com/datasheet-pdf/view/99624/PHILIPS/ISP1181A.html   B: http://pdf1.alldatasheet.com/datasheet-pdf/view/100621/PHILIPS/ISP1181B.html       So, this is kind of a generic question - what what kind of difference might you expect between these different revisions, and is it worth a punt to replace the B version with the A version and hope it will work? The unit is toast as it is, the worst case scenario is it will still be toast with an A chip installed, but I have to buy the A chip to find out.     Cheers,   Gareth.

ohger1s@gmail.com: Apr 05 04:39PM -0700 On Wednesday, April 5, 2017 at 6:20:18 PM UTC-4, Gareth Magennis wrote: > toast with an A chip installed, but I have to buy the A chip to find out.   > Cheers,   > Gareth.   It's close enough where I don't see it doing any harm if it's somehow not compatible. In fact, the datasheet seems to be a cut and past except for the A and B suffix.

oldschool@tubes.com: Apr 05 12:43PM -0400 On Wed, 5 Apr 2017 12:09:34 +0100, Adrian Caspersz <email@here.invalid> wrote:     >Do you really need the manual?   >-- >Adrian C   I probably dont really need the manual. I can understand the functions, but I wanted to know how much gain was used on different inputs, or if they are all the same. I can learn more by looking at a schematic than reading a lot of info.   But at this point, I am not wasting any more time looking for a manual. I'll just plug in a sine wave from my audio generator, and feed it to my oscope to see what the gain is.   I should mention that I am not using this thing for video. I am only using the audio portions to feed multiple inputs into an amplifier. All inputs are about the same sound levels, so that is why I am concerned about the gain.   I originally planned to build a switch box for this purpose. But the price of a "bud box" (aluminum box) a rotary switch, and a bunch of RCA jacks far exceeded the price of this Archer device. So, to save money, as well as time, I thought this was the way to go. The video portions just will not be used. (But I could use it for that purpose if I ever needed to). I really dont mind building stuff from scratch, but when it costs 3 or 4 times what it costs to buy something like this, there is no sense to it. Not to mention all the drilling I'd have to do to mount all the RCA jacks. (Thats the part I dont like).

oldschool@tubes.com: Apr 05 12:46PM -0400 On Wed, 5 Apr 2017 10:46:57 +0000 (UTC), Bruce Esquibel <bje@ripco.com> wrote:   >couple knobs was the 2nd best feature. After that, meh.   >-bruce >bje@ripco.com   Where did you hear about another RS bankruptcy? Can you provide any links to that?   See my other response in this thread regarding why I wanted a manual... And why I no longer will waste any more time looking for one....

Foxs Mercantile <jdangus@att.net>: Apr 05 01:03PM -0500 > Where did you hear about another RS bankruptcy? Can you provide any > links to that?   You honestly live under a rock don't you?   <http://fortune.com/2017/03/08/radioshack-bankrupt-chapter-11/>     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

John Robertson <spam@flippers.com>: Apr 05 11:46AM -0700 On 2017/04/05 4:09 AM, Adrian Caspersz wrote: > labels in & out, and yet fully manage to survive a trip to a supermarket > or the car park.   > Do you really need the manual?   https://web-beta.archive.org/web/*/https://www.radioshack.com   Go back to around 2005 (or other year - you need to hunt!), manual directories are there, some PDFs may be archived, and if you are lucky RS never deleted them from the server even if the link went away later - so you then try the "This Page Is Available on the Web" and see if it pulls it in.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

oldschool@tubes.com: Apr 05 01:47PM -0400 On Wed, 5 Apr 2017 13:03:30 -0500, Foxs Mercantile <jdangus@att.net> wrote:   >> links to that?   >You honestly live under a rock don't you?   ><http://fortune.com/2017/03/08/radioshack-bankrupt-chapter-11/>   I have more important things to do than watch tv.... Once or twice a day I turn it on to get the weather report. Thats about it. The rest of the news is just political garbage which is just mostly all hogwash words and lies anyhow....   Anyhow, thanks for the link! Now I know. Not that I can do anything about it.....

Foxs Mercantile <jdangus@att.net>: Apr 05 03:03PM -0500 > I have more important things to do than watch tv....   What makes you think I watch television?     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

oldschool@tubes.com: Apr 05 05:18PM -0400 On Wed, 5 Apr 2017 15:03:10 -0500, Foxs Mercantile <jdangus@att.net> wrote:   >On 4/5/2017 12:47 PM, oldschool@tubes.com wrote: >> I have more important things to do than watch tv....   >What makes you think I watch television?   I can see the picture tube on your forehead :)

John Robertson <spam@flippers.com>: Apr 05 12:03PM -0700 On 2017/04/05 7:13 AM, Foxs Mercantile wrote: >> Are you trying to replace a unit, or looking for historical information?   > Like having a RCA tube manual so you can tell the difference between > a 12AU7, 12AX7 and a 12SN7.   My old Electrosonic distributor parts catalogue goes back to 1968 and does have some mercury wetted relays, but not your brand I'm afraid - Potter & Brumfield. If you are just looking for specs on this style of relay I can email you a scanned page or two. There is little detail, mostly just a list of the relays with a bit of an explanation as t their ratings   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Foxs Mercantile <jdangus@att.net>: Apr 05 03:02PM -0500 On 4/5/2017 2:03 PM, John Robertson wrote: > email you a scanned page or two. There is little detail, mostly > just a list of the relays with a bit of an explanation as to > their ratings     Yes John, that would be greatly appreciated. The email here is good.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

John Robertson <spam@flippers.com>: Apr 05 03:07PM -0700 On 2017/04/05 1:02 PM, Foxs Mercantile wrote: >> their ratings   > Yes John, that would be greatly appreciated. > The email here is good.   You have mail!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

John Robertson <spam@flippers.com>: Apr 05 11:53AM -0700 > a living room, a long balcony, and a kitchen. Canadian hospitality, > gotta love it. > Eric   My wife and I went down twice to the US (Burlington area) to adopt a rescue dog (A nice Saluki!) and both times the border crossings were under 20 minutes. This was on the last two Wednesdays in March. Weekends can have long lineups - sometimes up to an hour. Holidays are worse. There are signs showing you an estimated wait time as you approach the border (both sides) and you can go one of the two alternate truck crossings where the time may be shorter.   Hope you like playing pinball!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

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