Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x


Quiet 42-380
#1

Hi All.  As the subject says, I'm working on a 42-380 that is very quiet.  I've replaced all caps and some out of spec resisters.  Powered it up and got nothing.  Check voltages and with my variac at 112 volts all voltages are right on the money.  All the tubes have been tested and are good.  I did have to sub the XXLs with a 7A4 and a 7B4 which pretty much the same thing.  It is oscillating.  I checked it with another radio.
  I noticed that on the schematic the antenna coil, it says is from point 1 to point 4 should be 150 ohms.  My antenna coil only measures 4.5 ohms.  Is the schematic wrong or do I have the wrong antenna coil.  It looked original.  I even took all 3 IF cans apart and checked everything inside them and changed 1 resister in the third IF can.
  So my question is, has anyone experienced this problem and does anyone have any suggestions as to my next move to get this thing running.
  Thanks for any consideration,

  Dick
#2

check the band switch may need to clean it
#3

Try to put modulated RF sig from your oscilaltor. See if it passes at all.
Maybe at IF frequency.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#4

I think I found the problem.  I usually leave mica caps alone but I found one under the preselect assembly that happened to be a Micamold.  It actually measured close to what it was supposed to be. I changed it anyway and the radio came to life.  All I can think is that cap must have opened up as soon as power was sent to it.  The radio ran for an hour with good selectivity and lots of volume.  Amazing that such a small thing can stop a radio in its tracks.  Thanks

Dick




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco P45-6365 Universal Transformer Instruction Manual
Can anyone guide me to where this may be found?GRG — 03:00 PM
54C Complete Teardown/Rebuild
I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM

[-]
Who's Online
There are currently 2690 online users. [Complete List]
» 2 Member(s) | 2688 Guest(s)
AvatarAvatar

>