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Re: Tektronix 145 PAL test signal generator - repair (oven control circuit and maybe more)
Hi all
Thanks for your inputs... yes it's mostly for preservation reasons... how many people or institutions are left with a functional Tektronix 145? I initially picked it up for spares but it's so well made it would be sad to trash it if repair is possible. If I can't get the crystal oven to work or other BER situation I can still gut it. I do have old PAL televisions to repair/restore so it could also theoretically serve a purpose. I'm not sure replacing the resistor will help with anything.. it reads within spec, is ¡ãC 130~ too hot for a larger resistor? I checked all the socketed transistors and they're OK. The thermistor is not open, though I'm not sure about its value (I should probably remove it out of circuit to check). I will have a look into the power supply section and try to get it within spec before I continue. After 30 mins of waiting, the TP1100 voltage stopped at 3.95 V (the manual says it should come on before 20 mins - the recommended warmup time). Maybe it does need the PSU section dialed in. |
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Re: Extender Card for TM500/TM5000 with Test points on every line.
I have my boards made at PCBWay. They produce extremely high quality boards at very reasonable prices. When gold fingers are involved using the traditional gold over nickel the fingers are electroplated which takes extensive time and Gold is EXPENSIVE. The difference in cost between the 5 board minimum and 25 boards is only about $35, once you cover the extra setup. If I pursue the project, they will also do a 30 degree bevel on the finger end of the board to allow it to fit into the female connector easily. I am investigating a less costly but still rugged finger treatment called Enepig (electroless nickel electroless palladium immersion gold). This finish is cheaper to apply than the the electroplated gold over nickel, but still make a set of boards in the $150 + range instead of the $20+ range.
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Another expensive item is the Female connector. I plan to use the Sullins ECM28DRKN-S!3 which can be ordered from Digikey for $10.72 each, but minimum order is 10 pcs. This very high quality connector uses full bellows Gold over Nickel phosphor bronze contacts. The contacts and the plastic are rated at 125 degrees C. The gold plated 4-pin headers are not cheap, either and 56 of them are required for each extender board. FCI part number 95293--101-04LH (30u" gold over NI) or 95283-801LF (15u" Gold over NI). The Jumpers are also expensive: FCI 65474-001. 56 required, 60 recommended in case you lose a couple. The design is very high quality, but as a result it is not cheap. Actually the construction will be superior to the male end of my Tek 067-0645-02 TM500 extender cable. The male end of their cable did not have the 30 degree bevel which makes it much harder to insert into a female connector than the typical plug in. I am continuing to research the costs for this project, but it is not going to come in at the $50 price of the one on eBay that uses raw copper for the board and fingers, with no test points. Hopefully there will be enough interest to group buy the parts. Steve On 2025-02-18 10:22, Roy Thistle via groups.io wrote:
On Mon, Feb 17, 2025 at 12:56 PM, Eric Garner wrote:Not to dissuade OP from their projectWell... many of us...on this forum... IMO... are hobbyists. |
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Re: Tektronix 145 PAL test signal generator - repair (oven control circuit and maybe more)
Luca,
R1156 is too hot. Replace with a 5W. Look around the TP1100 for bad parts. The thermistor could be open. Dirty pins/sockets could be the problem. Check the ripple in the power supply. At the age of this unit, recapping may be necessary. Mark |
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Re: Tektronix 145 PAL test signal generator - repair (oven control circuit and maybe more)
To fix PAL standard televisions?
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Yes, people are into preserving antique televisions and equipment. Now if 145 PAL does not refer to test equipment for the non-NTSC standard televisions them I am out. Frank DuVal On 2/19/2025 11:44 AM, EB4APL via groups.io wrote:
Excuse me, but why you would want a functional PAL signal generator? |
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Re: Tektronix 145 PAL test signal generator - repair (oven control circuit and maybe more)
Excuse me, but why you would want a functional PAL signal generator?
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El 19/02/2025 a las 17:31, Luca via groups.io escribi¨®:
Hi all --
Este correo electr¨®nico ha sido analizado en busca de virus por el software antivirus de Avast. www.avast.com |
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Tektronix 145 PAL test signal generator - repair (oven control circuit and maybe more)
Hi all
Here /g/TekScopes/topic/107425848 H?kan kindly provided the service manual for this signal generator. I had time to have a look inside and found a shorted cap on the -15V supply (C1200 of A13 board), now the power supply seems to behave a bit better (the 3.6 V rail is still off, at 3.3~ ish Volts) According to the manual the oven temp normal light should come on but this never happens (this circuit doesn't seem to use the 3.6V rail so I ignored it for now) The manual says that TP1100 should be around 4.1-4.2 Volts for the "oven temp normal" light to come on but that never happens.. it hovers around 3.5 V and varies a bit. I noticed that R1156 gets really hot (>100 ¡ãC) but I don't know if this is a fault or not. I took the oven apart to check the thermal fuse but it seems ok... so I'm not really sure where to go from here. I updated the album: /g/TekScopes/album?id=296482 Can I plug the oven in without enclosure for testing? Disclaimer: I obviously have no idea what I'm doing... there doesn't appear to be any notable occurences of this SG on the net so I will try to find faulty or out of spec parts and hope any of you have a good idea where to start Thanks Luca |
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Re: electronics help?
Hi All,
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The items are mainly TM500 / 5000 series plug ins and 7000 series scopes and plug ins... Most of which I believe were purchased from the Tek Country store over the last 2-3 decades. She already has a buyer; I'd suspect you will see some of this stuff at the local PNW Ham Radio / Electronics swapmeets soon.??Nothing that is usable will go in the trash.?? Thanks,?Ryan On Friday, February 14, 2025 at 08:23:11 AM PST, icy.dev via groups.io <icy.dev@...> wrote:
Ryan, Please post a list of what she has available!!! Esp if close to Portland. My daughter is there and can pick up for me!!?? |
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Re: KO4BB Manuals not working?
Funny, When I google ko4bb and click on Manuals, I can get to any manual that is a file listed on that page. But if I click on a folder, then it goes to Home page.
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Frank DuVal On 2/18/2025 5:46 AM, Tom Gardner via groups.io wrote:
On Tue, 18 Feb 2025 at 06:23, Sam Reaves via groups.io <sam.reaves= |
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Re: Extender Card for TM500/TM5000 with Test points on every line.
On Mon, Feb 17, 2025 at 12:56 PM, Eric Garner wrote:
Well... many of us...on this forum... IMO... are hobbyists. Probably, I am not very smart... but AFAICT... time, connectors, and fiddling around with shipping, can be expensive... but, high quality PCB are not. On way around the distribution problem is to register a 'project' with a PCB manufacturer, and then anyone can order the PCB. Also, at least down to common components, the PCB manufacturer can also manufacture the thing to that level, and even provide a kit. The connectors for these...ARAIK... are not as much of a problem sourcing anymore. If one is worried about quality, and not their wallet... then buying the Tektronix ones... when they show up... might be a better solution. -- Roy Thistle |
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Re: Extender Card for TM500/TM5000 with Test points on every line.
On Fri, Feb 14, 2025 at 07:49 PM, <info@...> wrote:
Hi: AFAIK... there have been a few projects about/similar to this. If you have the time, and the desire... can you explain why they cost 150.00 each? -- Roy Thistle |
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Re: KO4BB Manuals not working?
On Tue, 18 Feb 2025 at 06:23, Sam Reaves via groups.io <sam.reaves=
[email protected]> wrote: Does anyone know what is going on with ko4bb,com? The owner has been having capacity problems. Due to that I would only make sparing use of a workaround: |
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Re: Extender Card for TM500/TM5000 with Test points on every line.
Not to dissuade OP from their project but Dan Meeks on this list may still
have some of his kits for extenders that were sub $50 USD last time I bought one On Mon, Feb 17, 2025 at 12:50?PM 2notlit via groups.io <2notlit= [email protected]> wrote: Ditto on what Arne Buck said. Interest is for one extender board unless-- --Eric _________________________________________ Eric Garner |
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Re: 7D20 on EDN Magazine Cover
I also had some years ago my right eye done. It took me about three hours in the clinic all in all.
Perfect result. My left eye is only slightly yellowish like the right was but the color temperature is hardly noticeable. What was bad essentially on the right was much dazzling. My right plastic lens is much better than the original one. I concur that if one need it, do not hesitate to have cataract surgery. Best Renaud |
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Re: 7D20 on EDN Magazine Cover
I am glad to see this response. I am due for implants soon so its certainly of value to me. Missed my appointment due to flu but due for exam by surgeon in a couple of weeks. I have fairly advanced cataracts. Pictures of the inside of my eyes show them plainly. I was fooling myself they were not that bad but now realize just how bad my vision has become. I know lots of people who have had cataract surgery and lens implants, all seem to be very happy with them. I will have fixed distance vision installed. I've had experience with bifocals and trifocals and hated them. Don't mind reading glasses at all. Exam I had showed that beside the cataracts my eyes are healthy.
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On 2/16/2025 2:39 PM, ken chalfant via groups.io wrote:
Greetings, --
Richard Knoppow Los Angeles WB6KBL SKCC 19998 |
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Re: 7D20 on EDN Magazine Cover
Greetings,
I¡¯m a little off topic and not certain if I intend this message for Clark F or Kurt R. Perhaps my comments may be a value to others. I was inspired to comment based on reference to ¡°yellow cataract vision¡±. I suffered with advancing cataracts for far too long. I kept telling myself that it really wasn¡¯t that bad yet. Finally, my charming child bride, who had become very uncomfortable riding with me when I was driving convinced me to have the surgeries. From my perspective I was amazed how easy it was. I showed up, they gave me some ¡°happy juice¡± and when I woke up the view out of the eye they had just repaired was amazing! I had actually forgotten what white looked like. Everything had slowly turned yellow, and I had no idea how extreme the color shift was. A few months later I had the other eye surgery with equal success. Technology has come a long way. When I was a kid in the 1950¡¯s and 1960¡¯s the older people I knew who had had cataract surgery wore truly Coke bottle bottom thick glasses. That¡¯s not the case any longer. There are many different choices of IOL (Inner Ocular Lenses). The main options include: monofocal lenses (standard choice), toric lenses (correct astigmatism), multifocal lenses (for multiple vision distances), extended depth of focus (EDOF) lenses (improved intermediate vision), and light-adjustable lenses (post-surgery customization); with the best option depending on your individual vision needs and whether you want to minimize reliance on glasses after surgery. Since I need flip-down magnifiers for small work anyway I chose a standard monofocal distance vision lens. OK - forgive me for typing a lot of words. I just wanted to share that in my opinion cataract surgery is a wonderful procedure that made my life so much better. The bonus is that my wife is once again comfortable when I¡¯m driving. If any of you are putting off cataract surgery for whatever reason - and I had mine - don¡¯t wait. Get your vision back! Regards, Ken From: [email protected] <[email protected]> on behalf of Clark Foley via groups.io <clarkfoley@...> Date: Saturday, February 15, 2025 at 4:19?PM To: [email protected] <[email protected]> Subject: [TekScopes] 7D20 on EDN Magazine Cover A photograph that was used for the cover of EDN magazine was posted to the Tek wiki site today. The photograph was published in November 1982 to support the introduction of the 7D20 and to reinforce the modularity of 7000 series. I apologize for the color balance. The photograph was badly faded to orange. I made a color correction but with my yellow cataract vision, I over emphasized the blue. Thank you Kurt R. for posting the photograph. <> |
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