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

Philco Tropic 46-888 E.Z. Restoration
#13

The rest of the capacitors were restuffed and reinstalled. Any out of tolerance resistors not yet replaced were replaced. All of the original tubes that tested good were replaced, and any bad ones replaced.  A new power cord was attached.  I assumed that flat brown vinyl (likely originally rubber) is appropriate for 1946. I then carefully examined the chassis for unsoldered joints and solder blobs. I then checked once again for any B+ shorts. The speaker was plugged in, and an antenna wire attached. I pulled the rectifier tube and powered up the chassis using a Variac through a watt meter. I started at zero volts and gradually increased the line voltage while watching the watt meter. All the tubes lit up and current draw was normal.
 
I then reinstalled the rectifier tube and monitored B+ with my DVM.  I again powered up the chassis with my Variac through a watt meter while monitoring the B+. Power was increased at about 10 volt increments, allowing time for the new filter caps to reform. The band switch was set to the broadcast band and the volume control set a maximum.  At about 80 volts AC I heard some noise. I increased the AC to 115 volts. The radio actually worked on all bands. The volume control was smooth and free of noise.  The tone control, which was an area of concern, seemed to work OK although I’m sure not as well as it should, since the resistance had drifted from 6meg to 16megs! At maximum CCW, bass boost or loudness compensation was reduced.  As the control was rotated clockwise to about ½ rotation, bass increased. Further CW rotation reduced the treble.  So for most fidelity the control should be centered.  CCW rotation reduces the bass, and CW rotation reduces the treble. This seemed to agree with the schematic.
 
The next step is alignment of the two IF stages and 10 bands of trimmers! At this writing I have completed alignment of the IF stages and Shortwave #3 band. I was concerned about this band since my signal generator only goes up to about 12mHz with any stability. I have to use harmonics for adjusting anything above 12mHz. So to set the SW3 band to scale at 21mHz, I set the generator to 10.5mHz. I use a frequency counter to calibrate the generator. SW3 was easier than I thought it would be. Even the image frequency appeared where it should have been.  All that’s left is to complete the alignment, clean the cabinet, and reassemble.

Photos of the completed chassis are attached.


Attached Files Image(s)
           


Messages In This Thread
Philco Tropic 46-888 E.Z. Restoration - by davemc - 06-12-2016, 12:21 PM
RE: Philco Tropic 46-888 E.Z. Restoration - by davemc - 07-05-2016, 02:24 PM



Users browsing this thread: 5 Guest(s)
[-]
Recent Posts
Philco 60 Squealing
I got my signal tracer out to see if I could tell at what stage the squeal was coming from. It is present on the plate o...dconant — 09:07 AM
Philco 16B Parts
The 16B's in the tombstone cabinet sport a 10 1/2" spkr vs the older cathedral sets which uses an 8". The p/p ...Radioroslyn — 12:58 AM
Philco 38-7 Oscillation
I have let this one sit because of other duties. Now I am back, and I have a couple of questions. I hooked up a Hammond ...tludka — 11:16 PM
Philco 38-7 Speaker
I know that when I first started working on this radio, I did not even have a speaker. Once I finally found one it was n...tludka — 11:00 PM
Philco 60 Squealing
I seem to remember eliminating a squeal by changing the IF frequency by a few KHz. Not that you should put too much tru...fenbach — 08:48 PM
Philco 42-390, code 121 speaker
These speakers pop up on eBay regularly, even if at bloated prices. Honestly, have not seen many parts on swapmeets.morzh — 08:38 PM
Philco 38-7 Speaker
The put-put is not like the speaker problem.morzh — 08:29 PM
Mission Bell Model 19A Car Radio
Hello everyone,  As mentioned in my last post I was going to see if the vibrator / rectifier section could be persuaded...Antipodal — 08:21 PM
Philco 60 Squealing
Wondering if I did it backwards. If a coil was wound backwards, the oscillator would not work at all. Old school...Chas — 07:23 PM
Philco 38-7 Speaker
4-ohm speaker. Black, Green leads.tludka — 07:00 PM

[-]
Who's Online
There are currently 4562 online users. [Complete List]
» 4 Member(s) | 4558 Guest(s)
AvatarAvatarAvatarAvatar

>