sci.electronics.repair@googlegroups.com

Google Groups

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 29 06:39AM -0800 Some may know that part of my job involves the closing and mothballing of a major teaching hospital, of which the physical plant is every bit of 50 years old, or more.   Just the other day, a steam line blew, flooding a basement storage room with condensate - undetected for a week or three. Mold. In this room were stored two (2) Midmark Ritter 355 OR lights, sealed in their mold-ridden, but new boxes.   http://www.berktree.com/ritter-355-minor-surgery-light-8-.html I was told that it was between me and the dumpster. One went to me, one to our Vet.   This will involve a complete re-design of my Radio Room - together with a major Culling-of-the-Herd. And, since the house was built in 1890, I will have to be very clever with the installation. The thing weighs 62 pounds and the mount needs to be dead-level.   Not a bad task to be given.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Jan 28 10:41AM -0800 On Tuesday, 28 January 2020 15:37:22 UTC, Fox's Mercantile wrote: > On 1/28/20 8:16 AM, tabbypurr wrote: > > The 'how is ozone harmful' section is pretty iffy. I've not read furtheer.   > Maybe if you had read past the title.   The 'how is ozone harmful' section is a fair way past the title

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 11:32AM -0800 > The 'how is ozone harmful' section is pretty iffy. I've not read furtheer.   When inhaled, ozone can damage the lungs. Relatively low amounts can cause chest pain, coughing, shortness of breath and throat irritation. Ozone may also worsen chronic respiratory diseases such as asthma and compromise the ability of the body to fight respiratory infections. People vary widely in their susceptibility to ozone. Healthy people, as well as those with respiratory difficulty, can experience breathing problems when exposed to ozone. Exercise during exposure to ozone causes a greater amount of ozone to be inhaled, and increases the risk of harmful respiratory effects.   >snip<   Ozone is a toxic gas with vastly different chemical and toxicological properties from oxygen. Several federal agencies have established health standards or recommendations to limit human exposure to ozone. These exposure limits are summarized in Table 1.   >snip<     That is "iffy"? You are, truly, a 'piece of work'.   Peter Wieck Melrose Park, PA

bilou <bilou@sfr.fr>: Jan 28 08:45PM +0100 On 26/01/2020 02:52, J-J wrote: > a standard ballast.  How would I go about calculating incandescent size > and capacitance?  In the video, he is using 20 uF, but I think that's > for a much larger bulb if I'm not mistaken.  Thanks. The capacitor is here to correct the power factor of the ballast. For a test it is not necessary. For a 125W lamp it is an 8 µF. I used one of those lamps for lighting in the early ages of amateur video. It took several minutes to reach normal brightness. Today with LED they are useless. Even with their envelope intact those lamps are not designed to be looked at at close range . Use of sun glasses is a good idea.

tabbypurr@gmail.com: Jan 28 05:09PM -0800 > Ozone is a toxic gas with vastly different chemical and toxicological properties from oxygen. Several federal agencies have established health standards or recommendations to limit human exposure to ozone. These exposure limits are summarized in Table 1.   > >snip<   > That is "iffy"?   It reminds me of the dihydrogen monoxide gag, where a useful substance (water) is described as if it were a terrible killer that should be eradicated. It's like saying floods kill people in India every decade so we should not have tap water. It relies on the reader's lack of knowledge of the subject.     > You are, truly, a 'piece of work'.   I think that says more about you than me.     NT

Fox's Mercantile <jdangus@att.net>: Jan 28 07:52PM -0600 > It reminds me of the dihydrogen monoxide gag,   But we're not talking about dihydrogen monoxide. We're talking about ozone which does indeed have serious health effects. When I was a kid growing up in Los Angeles in the late '50s and early '60s, we'd have "ozone days". School was canceled. It hurt to take deep breath.   Peter is right, you are piece of work. You consistently ignore facts and continue to argue.   -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 29 04:29AM -0800 Jeff:   I have come to the conclusion that no reasonable person should stand in the way of any individual whose heart is set on earning a Darwin Award.   Peter Wieck Melrose Park, PA

John Robertson <spam@flippers.com>: Jan 28 10:31AM -0800 On 2020/01/27 3:41 p.m., John-Del wrote: > I have one of these old timers and the bar sweep and color sweep section isn't working. Strangely, there are color bars over the dot and cross hatch patterns which I don't recall being a normal situation. All the switches are clean and tight.   > Anyway, I have the full owner's manual that includes maintenance and calibration instructions, but no actual schematic.   > Does anyone have a schematic of the 500 generator board and parts layout for the same board? This is the only board where the component legends are not silk screened on the board, and there are at least 12 ICs - all 16 pins each, most of them the same number.   I'm looking at restoring the same device, and am also hunting for the schematics.   I do have a PDF of the VA48 Speed Test Set-Up Booklet and would be happy to trade that for schematics...(or simply upon being asked nicely)   On the other hand I see these selling on eBay for under $100 including shipping - vs the VA62 which is the updated version for not much more and I'm not sure I want to spend the time on it...especially as I already have the Sencore 1225 which is the most advanced of their monitor analyzers...   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."

amdx <nojunk@knology.net>: Jan 28 01:20PM -0600 On 1/27/2020 5:41 PM, John-Del wrote: > I have one of these old timers and the bar sweep and color sweep section isn't working. Strangely, there are color bars over the dot and cross hatch patterns which I don't recall being a normal situation. All the switches are clean and tight.   > Anyway, I have the full owner's manual that includes maintenance and calibration instructions, but no actual schematic.   > Does anyone have a schematic of the 500 generator board and parts layout for the same board? This is the only board where the component legends are not silk screened on the board, and there are at least 12 ICs - all 16 pins each, most of them the same number.   You might try asking on the forum. > http://www.videokarma.org/   Mikek

amdx <nojunk@knology.net>: Jan 28 01:38PM -0600 On 1/28/2020 1:20 PM, amdx wrote:   > You might try asking on the forum. >> http://www.videokarma.org/   >                      Mikek   Oh, I found a post asking for the VA48 schematic. It could even be you, first name is John! No response. :-( Mikek

John Robertson <spam@flippers.com>: Jan 28 01:00PM -0800 On 2020/01/28 11:38 a.m., amdx wrote: > It could even be you, first name is John! > No response. :-( >                             Mikek   Could be indeed!   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."

John-Del <ohger1s@gmail.com>: Jan 28 02:31PM -0800 Yeah, that was me...   BTW, if anyone needs any service for the VA62, *that* I have. Everything.   I technically own two VA48s now. Yep. I asked my buddy if he still had his manual and he said just take his VA48. I don't need two and I'd rather repair the one I have now.   Worse case I'll take the second one and compare waveforms between them, assuming his working fine..

John-Del <ohger1s@gmail.com>: Jan 28 02:45PM -0800 On Tuesday, January 28, 2020 at 1:31:45 PM UTC-5, John Robertson wrote: > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."       I have a few pages someone scanned, but the generator board is chopped up. Some of it is usable for some of the interconnections are not. I'll email over what I have.

amdx <nojunk@knology.net>: Jan 28 05:15PM -0600 On 1/28/2020 4:31 PM, John-Del wrote:   > BTW, if anyone needs any service for the VA62, *that* I have. Everything.   > I technically own two VA48s now. Yep. I asked my buddy if he still had his manual and he said just take his VA48. I don't need two and I'd rather repair the one I have now.   > Worse case I'll take the second one and compare waveforms between them, assuming his working fine..   I did some searching and didn't come up with any leads other than one post saying he got the schematic from Sencore 10 years ago for $20, but was sure what it would cost you today. Mikek

John-Del <ohger1s@gmail.com>: Jan 28 03:56PM -0800 On Tuesday, January 28, 2020 at 6:15:08 PM UTC-5, amdx wrote: > post saying he got the schematic from Sencore 10 years ago for $20, but > was sure what it would cost you today. > Mikek       I called Sencore, and they no longer support legacy items.

John Robertson <spam@flippers.com>: Jan 28 04:22PM -0800 On 2020/01/28 2:31 p.m., John-Del wrote:   > BTW, if anyone needs any service for the VA62, *that* I have. Everything.   > I technically own two VA48s now. Yep. I asked my buddy if he still had his manual and he said just take his VA48. I don't need two and I'd rather repair the one I have now.   > Worse case I'll take the second one and compare waveforms between them, assuming his working fine..   Ah, I have also posted on videokarma so we are both right   http://www.videokarma.org/showthread.php?p=3220162#post3220162   Let's see if the schematics turn up!   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."

John-Del <ohger1s@gmail.com>: Jan 28 05:37PM -0800 On Tuesday, January 28, 2020 at 7:22:40 PM UTC-5, John Robertson wrote:   > Ah, I have also posted on videokarma so we are both right   > http://www.videokarma.org/showthread.php?p=3220162#post3220162   > Let's see if the schematics turn up!   Check your email...

Peter X1 <ptro@xs4all.nl.invalid>: Jan 28 08:51PM +0100 > I had searched the web for a source about a year ago.   > Does anyone know where I can get a schematic?   > Thank You in advance, John   Guess this is the stripped/desk version of the 200XLT handheld. Manualslib has a service manuals for the the 200XLT   -- Kind Rgegards,   Peter OXzilla

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 08:51AM -0800 I would start over with an entirely new power-supply, if you are so-inclined. You will get better reliability, at least, than dealing with 20-30 year old components.   https://www.teslaboys.com/Plasma/PlasmaPower/index.html   http://amasci.com/tesla/sstesla.gif   ...of dozens of possibilities.   If your flyback is good, you may only need to "fix" the driver section.   Peter Wieck Melrose Park, PA

Tempestinatesttube <tempest@ina.com>: Jan 28 11:58AM -0500 > If your flyback is good, you may only need to "fix" the driver section.   > Peter Wieck > Melrose Park, PA   That was my thought (new flyback supply) if I couldn't get the current one working. The flyback is a smaller one and reminds me of the kind used in portable TV's of the past. I may try taking readings of the HV in the borrowed unit as I have a HV probe, but from experience this may or may not be successful depending on how much the probe loads the circuit.   I'm going to have to take resistance readings of the flyback in the borrowed unit and then compare them with mine.

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 09:32AM -0800 ... this group exists to teach people the hard way of doing things - rather than the correct, effective or efficient way.   Anon.   a) Verify the flyback as correct. This can be done cold with simple resistance readings. b) Verify the power-transformer. This can also be done cold with simple resistance readings. c) Build a new power-supply - looks like about US$10 worth, including the heat-sink. Less transformers, of course, if needed. d) Even both transformers should be able to be had for less than US$20.   If you start screwing around with the borrowed unit, you may have two dead devices on your hands. By your own admission, you are not a highly experienced expert in these things, so I am suggesting you err on the side of caution.   Peter Wieck Melrose Park, PA

Tempestinatesttube <tempest@ina.com>: Jan 28 01:58PM -0500 > If you start screwing around with the borrowed unit, you may have two dead devices on your hands. By your own admission, you are not a highly experienced expert in these things, so I am suggesting you err on the side of caution.   > Peter Wieck > Melrose Park, PA   Good points, thanks. Once upon a time, I had a nice Tek scope, but that was over 20 years ago. Resistance readings will have to do.   The good news is that I have all the flyback parts in drawers, including small flybacks, in the event I decide to build a new flyback supply.   By the way, one thing I don't like seeing is no power transformer. I believe this was line powered. Ouch!

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 28 11:24AM -0800 On Tuesday, January 28, 2020 at 1:58:26 PM UTC-5, Tempestinatesttube wrote: > By the way, one thing I don't like seeing is no power transformer. I > believe this was line powered. Ouch!     Line-powered to the flyback - which isolates as well.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Jan 28 10:40AM -0800 On Tuesday, 28 January 2020 15:32:31 UTC, Fox's Mercantile wrote: > On 1/28/20 8:12 AM, tabbypurr wrote: > > And yes, an easy fix it is.   > And what was that?   just an o/c connection, and the cook switch contacts needed a clean.

You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to sci.electronics.repair+unsubscribe@googlegroups.com.