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

41-280 pushbutton station selection fine, no oscillator output on manual tuning bands
#9

Well... I've learned a lot reading this forum, and acquired a replacement speaker from one member, so I feel compelled to close out this thread with an accounting of "how it turned out". Perhaps others can learn from my experience. It wasn't a bad oscillator transformer and fortunately I figured that out before I removed it from the circuit.

While ohm'ing it out in-circuit, looking for anything other than a fractional ohm between terminals, I noticed that cap #31 was connected to the wrong terminal on the terminal block mounted to the chassis side wall. One pin off, resulting in connection to chassis ground instead of a leg of the 1st I. F. transformer.

Fixed that, and voila, manual dial tuning works.

Now, I replaced that cap back when I recapped the unit. So -- although I'm not the first person to be doing repairs in this unit and it didn't work when I got it -- I have to conclude that I misplaced that cap when I replaced it. A real head-shaker, since I triple checked every cap I swapped out.

I used to tell the scouts in my BSA troop that every mistake is a learning opportunity, so here I'm concluding that comparing before and after photos after *every* component replacement is the rule from now on.

I'm refinishing the cabinet next and have a question about speaker grill cloth, so I'll post that on the other forum.





Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 42-345 Restoration/Repair
Ok MrFixr55,  I have tried the DeoxIT D5 on the band switch and even though it has relieved the tension I felt when turn...osanders0311 — 11:11 AM
Part numbers to model cross
Is there a reference somewhere where you can punch in Philco part numbers and see what models those parts were used in?Jim Dutridge — 10:17 AM
Philco 42-345 Restoration/Repair
Hi OSanders, Look carefully at the band switch. Turn it slowly and "wiggle" it around the desired band. ...MrFixr55 — 12:33 AM
5U4 vs 5Z4 tubes
I think that RCA and GE introduced metal tubes in the USA in 1936.  I don't know if they were being made by RCA, GE or b...MrFixr55 — 11:20 PM
Philco 42-345 Restoration/Repair
Vlad95, Thank you for the stringing guides and wow there are so manyosanders0311 — 06:01 PM
5U4 vs 5Z4 tubes
A pre war Hallicrafters, and an early one too, very nice! 1936 is pretty early for metal tubes too, which would explain ...Arran — 05:58 PM
Philco 42-345 Restoration/Repair
Thanks Rod, "When you hear the background hiss and no station it usually indicates that the oscillator quit" ...osanders0311 — 05:52 PM
Philco 42-345 Restoration/Repair
RodB :beerchug:Vlad95 — 10:22 AM
Philco 42-345 Restoration/Repair
Vlad, you nailed it. Swiss and German roots.RodB — 09:54 AM
5U4 vs 5Z4 tubes
Well this is a Hallicrafters SX/9 circa 1936. No real issues so far although I dodged a real bullet with a cap that was...bridkarl — 07:59 AM

[-]
Who's Online
There are currently 1447 online users. [Complete List]
» 1 Member(s) | 1446 Guest(s)
Avatar

>