Sylvania console

[DaveWM]

Charlie I bet you are about ready to swim in...

don't you have some hot TV prospects waiting on your return?

I am waiting for some pics of an alleged (tube type console) I know she prob means CRT but I am hoping.... she did say uses tubes as in plural.

[Charlie]

I've got a few phone numbers written down here.

[Charlie]

Dave:

I am home now...


and have Sams 1503-2 in my hands... ready to mail. Send me an address and I'll get this out to you in the morning.

Also, just had a great visit from Reece... he just left a few minutes ago... all the way from Pennsylvania. I always enjoy visits from other VK/AK members!

[Reece]

It was great visiting Charlie and his TV shop in the works, a whole separate building that's going to be a shop of all shops! He has a beautiful location in the middle of a big clearing in the piney woods of East Texas. Thanks, Charlie.

[DaveWM]

I was just letting Charlie know that deflection circuit current HURTZ....

Big time, major ouch, umpa humpa, yowza....YIKES....GOLLY GEE!!!!!!

dab nab it, I was putzing around near the defection board and literally got zapped I mean fire baby, noise, the whole nine yards....

I have a nice scorched earth mark on my palm. Must respect TV power...

[Charlie]

I got zapped once years ago... by a 23" b&w tube... with the set off... and wow that was impressive!!! DID NOT feel good at all!

[DaveWM]

Got the Sams today (thanks Charlie!) boy is this thing complicated, but at least I have a starting point. I will start by going back to the CRT and checking the voltages now that I know what to look for, then I will check the Blanking/Inverting (that was called out when low or excessive brightness) I have voltage readings for the chroma board so I hope it can be narrowed down. If an IC is bad I guess I will be SOL unless these are common and easy to find, but they look propriatary (video processor) oh boy...

[Charlie]

<laughing> Yeah I thought that looked very complex compared to what I'm used to looking at!!! Probably not as bad as you'd think once you've spent a little time with it (i hope).

Your set does not seem to have the interesting control panel as shown in the Sams... perhaps that's a blessing!

[DaveWM]

I was lucky it has an old fashioned turret tuner, I stay away from push button tuners.

[DaveWM]

def something wrong, the crt cathodes should be about 175v all are at 220, so I am sure that is why its cut off. The driver transistors have the correct voltages at the base and emitter, but the collectors are also high (the collector connect to the cathodes).

I checked all the voltages from the ps all check fine. I will next get the scope on it and start checking waveforms, starting with the blanking signal.

IF i has an ESR meter I would just shot gun check all the little electros, but my cap tester only checks out of circuit so I would rather narrow it down.

I am going to have to pop for on of those in circuit ESR meters...

[DaveWM]

Really starting to hate this thing

I spent a couple hours checking voltages on the pins of the transistors and the IC's got a couple odd readings (should be 18v is 1.5v) not that that helps any, I mean ok I have odd voltages, now what. the one voltage is on a pin of an ic that I have no way of knowing what to do next. I guess if I had a replacement IC I would pop it in, but alas not like tubes or transistors.

I did check the resistance checks they were ok. argh, how do you guys deal with this stuff.

My last resort will be to check/replace everyone of the little electro caps on the chroma board, but again who knows could be the dumb IC.

[DaveWM]

oh and while testing it did make a pop sound, and what little bit of raster that would show up on the very edges of the crt is gone now. I dont know where the pop sound came from, nor do I see any evidence of blown parts. It was louder than just a HV spark. I still get a flash of light when turning the set off, and can hear the HV come up and there is still a faint raster that can only be seen in complete darkness.

[ctc17]

Transistor and ics pop and have a very pleasant aroma they release. Are you sure you didnt slip with the probe and touch two of the pins together? Dont give up, im sure you can find that ic somewhere. Inspect closely with a magnifying glass for crack or little holes

[DaveWM]

dont think it was me, I was not probing at the time of the pop.

I have a pretty good IC source near by (skycraft) will check them next week.

the voltage on the blanker transistor are wrong the base should be .06 its .6 all kinds of odd stuff going on here, again perhaps a wholesale check of the caps is in order. I did find one of the ic's online ECG791 AND ECG809. I think the nte791 and nte809 are the same thing, found them.

I am wondering how common are these, maybe I can find them in some old VCR's ect...

[radiotvnut]

NTE and ECG are the same as far as the numbers go. Chances are excellent that you will be able to get them. Many of them are still made.