Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

setting pushbuttons on a 42-390
#1

Old Farmer says hi,
    I've been setting the pushbuttons on a 42-390.  3 of them I could tune them into a station quite easily and they work real good.  2 of them, I'm lost !  By now, I've screwed the coil & cap.  So many times I don't know where I'm at. The best I could do was a very weak station that you could barely hear. Is there a better procedure other than just screwing back and forth and hoping you can catch something. On the fm antennae jack I see 2 extra holes. That wouldn't be some sort of aid to help set up these buttons?  Is there anything that I should be looking for.?
     RESPECTFULLY YOURS
  Steve
#2

Welcome to the phorum.
Icon_wave

I've not set them on that model but there is a service bulletin #398 that has some info.  The link to a djvu version is HERE.  the site also has a link to download a browser helper to open djvu documents.   There are specific frequency ranges for each of the 5 broadcast pushbuttons so there has to be a good am station in each of the ranges to get something on all of them.  its also possible that the coil in the button circuit has broken and that would kill that button.

UPDATE: Here's a direct link to the pdf version of the service bulletin: LINK
#3

HI Bob,
   Thanks for the pdf link. I was getting bogged down trying to get the file the other way.
     Tonight I put a wire coil inside the antennae and tried to slowly move the signal  generator up and down the frequencys.  Nothing, but, I could jam 455 khz through it. I think you might be right about the coils.  Time to pull out the chassis and verify the bad news.
  Thanks for the advice,
   Steve
#4

What I've done because sometimes it's hard to tell if the oscillator is running and where it's oscillating is use a counter to watch it. One of those $10 counters with a couple of turns of hookup wire connected to it looped over the osc tube should be able to get a reading.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#5

Hello,
   I wanted to get back to you and tell you guys what I found.I put 8 loops of #18 wire around the osc. tube. It wasn't  enough to get a real accurate reading with my counter, but you could sure tell if it  was working or not.. Found the coil & cap. leads on two buttons switched around.Easy fix !!!
    Thanks for all the advice,
   STEVE
#6

Icon_thumbup




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Restoration of the Canadian General Electric A-87
Thanks for your help Michael. In fact, this video is only an intermediate result. Later I had to apply another tinting l...RadioSvit — 09:01 AM
Restoration of the Canadian General Electric A-87
Great job on the cabinet. PS. In the US notation, "kenotron" refers to specific type of tubes; we call re...morzh — 08:24 AM
Part numbers to model cross
This document has at least some tables of models and parts used. Example: Choke 32-7572, used in 604 radio. Search f...morzh — 08:19 AM
Restoration of the Canadian General Electric A-87
I also checked all the radio tubes on my Hickok 530 tube tester. The 5Z3 kenotron turned out to be faulty, all the other...RadioSvit — 08:02 AM
Restoration of the Canadian General Electric A-87
Well... While the varnish is drying up, I started repairing the chassis... Of course I started by replacing the pa...RadioSvit — 07:12 AM
Philco Model 38-7: what caps & resistors do fail typically?
Hello Martin, Welcome aboard our little community what great Model 38-7 Sincerely Richardradiorich — 12:30 AM
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum Martin. I count about 9 paper caps, the 3 electrolytic caps and 2-Y2 safety caps to replace th...RodB — 09:44 PM
Part numbers to model cross
Jim, We have this index put together by Dale Cook but I don't think that is quite what you are looking for. The Parts...klondike98 — 09:37 PM
Philco Model 38-7: what caps & resistors do fail typically?
Yep the dim bulb test is OK but I'd definitely replace all those electrolytics before I did it. Since those #47 conden...klondike98 — 09:18 PM
Philco 42-345 Restoration/Repair
The resistor is a 2.2 Meg, it was the last one I hadn't replaced. The broadcast is coming in after replacing it.osanders0311 — 09:09 PM

[-]
Who's Online
There are currently 1061 online users. [Complete List]
» 1 Member(s) | 1060 Guest(s)
Avatar

>