I have a 214 I got quite a while back, and have replaced the batteries, the mode switch (store/norm/single sweep, etc). However, the vertical amp on channel 1 seems to be off by a lot. IIRC (and it's

Thank you to everyone. I now have ideas of where to look. I probably have more than one problem. I will continue to troubleshoot in a few days. Gary

Hi All: I ran into a guy who owned one of the service companies that used to supply rebuilt CRTs for televisions... it was a good business for about 15 years. Basically, he would rebuild (install a

Does anybody know at which addresses the number of power cycles and hours of operation (in TDS3000B series) are stored in the DS1742W NVRAM? and what is the format? I remember I saw that information

For what it's worth, the Early Television museum has the facilities to do rebuilding, just not the staff nor time to do it full-time. If they get that online though, odds are the Tek folks will be

Those who have been posting about replacement Tek CRTs, you may know of the Sphere Research "Stuff Day" sale. Walt Shawlee has Tek CRTs available both used and new. Here's the

I thought about that, especially re. Q722 just being two diodes. Next, since Gary mentioned he had checked all parts, I thought he'd checked them for what they are supposed to be. That left the

Hi Bob- Thanks for adding all of that good info! Good assessment of the weigh-1-or-2 piece issue. I can move the two pieces of a 555 much easier than the single piece of the 556. I need to have an

Raymond wrote: "What about my suspicion of R776 or its connection to R775 being open? It would result in about - 7V (6.2 + 0.7) V at the output, which Gary has observed." Yup, that would do it too -

Ed, What about my suspicion of R776 or its connection to R775 being open? It would result in about - 7V (6.2 + 0.7) V at the output, which Gary has observed. Raymond

Gary, I believe this is easily explained by looking back at the parts list where it says R773 and C773 were discontinued at Serial Number B049999. There is a discrepancy between this PDF of the

Or you can replace the backlight with white LEDs.     Mark Jordan

OK, so with partial output to -7V, then it's likely the voltage on VR772 is stuck way too low (failed or dumped by C772), or Q772 is breaking down or leaking. If Q772 went open, it would go open loop

You know David, it is so sad, it's almost funny. One of the instruments that I work on (non-oscope) used a backlight inverter similar, but different, to the backlight converter used in the TDS3000

Long ago, I did business with Thomas, a first class outfit. They needed glass for re-building a special tube they sold and I had a lot of it, so I traded twenty duds for two rebuilt tubes. They re-gun

I gave my opinion on this a few posts ago. If I'm not mistaken, Q788 is in full conduction by R787 pulling to gnd, *unless throttled* by the regulating circuits. Raymond

... and it would result in about - 7V (6.2 + 0.7) V at the output. BTW: Sorry for the concatenation of short posts. I had intended and started to do something completely different but came back to

Do you have enough access to make live measurements in this section while it's hooked up and powered? If so, you should be able to check some operating voltages and find the problem. Is the -30V zero,

Looking over their web page FAQ they claim to do around 50 different phosphors.I also sent them a note from there contact listing. I'm thinking at this point that cost will be the big factor.

... What about R776 or its connection to R775 being open..? I know you checked everything but the mystery remains... It can't be a shorted R777, because you said that adjusting R775 does nothing. A