View Full Version : Hoffman T1919


Rich12
10-11-2016, 11:42 AM
I've been bringing a craigslist find back from the dead. The owner told me it was stored in an attic for 35 years or so. I now have a raster, static and decent emissions on the picture tube, where I had none before. I'm guessing that these sets were so tightly fitted that the slightest moisture or temp changes knocked a lot of resistors out of whack. So it's been recapped and more than a few resistors have been replaced. My problem is that I just can't get a signal for picture or sound? The tuner appears to work fine, switches channels ok, etc. I'm guessing that's where the problem is? I did drop it and pop off the cover, cleaned it up as best I could. Before I try taking it apart I was looking for any suggestions as to where else to look. I tried both a VCR and the local cable box with no luck on pic or sound. Thanks for any suggestions.

Electronic M
10-11-2016, 12:08 PM
Wiggle /pull tubes in the IF stages and tuner. Start at the nth IF and count down to the first...If you get change in snow, or audio noise then you know that tube is passing signal. If you get noise pulses all the way back to the tuner (changing channels also ought to do it) you can assume those stages are working in some way.

Have you verified your signal sources work with another CRT based set using the same RF output from your source? It is possible that both sources are not properly set to output RF.

A B&K 1075/76/77 series analyzer is ideal for troubleshooting TV signal chain issues (among many other things)...If you plan to work on many TVs I recommend getting one.

Rich12
10-11-2016, 01:12 PM
thank you I will double check the tubes. The tuner does appear to be working ok, I do get a noticeable change in snow and static. I have a 1077B that I was setting up to test when a resistor sparked and started to smoke. I've got one on order that should be here in a week or so. I'll post my results when I get it back up and running. I always wonder if I'm missing something that is simple and obvious.