06-14-2016, 06:31 PM
http://www.radioatticarchives.com/radio.htm?radio=8951
The RCA Stratoworld was RCA's answer to the Zenith T/O. This one on the bench is from 1953. Fixing it for friend it came in unmolested abt 5 or 6yrs ago. I took a quick look at it then and after some troubleshooting found what I thought was a bad 1st IF transformer. Fast forward to now. Got it up on the dining room table started to sort it out. Plugged it in and gave it a go. Had audio hiss with some pops and level changes. So went through and replaced the caps in the audio stages. Helped a little and cleaned the controls too.
Applied a 455kc signal to the grid of the IF amp tube and received a signal from the spkr. Did the same to the plate of the mixer tube (1L6) read very expensive toob) All was well. Tried the input grid of the 1L6 and got nothing. Hmmmm. Should be able the pass a signal. Check voltage and look pretty good. Unfortunity my old wartime I-177 tube tester won't test a lot of these modern 7 pin toobs.
Did some research and found that you can use a 1R5 (read cheap battery toob use in just every portable made in the 50's and 60's that don't have a 1L6) with a modification. (remove pin 5 from the tube). Dug a 1R5 and off came pin 5. Carefully inserted in to the set and gave it a try. Well the 1L6 was bad the 1R5 caused it to spring to life.
So now it's working still is albeit noisy but still several bumblebee cap that need to go. Friends job is to come up with a good 1L6!
Ordered a bunch of mylar caps, resistors, and a few micas. So I'm waiting for them to show up to finish this and that Philco 42-854
Terry
The RCA Stratoworld was RCA's answer to the Zenith T/O. This one on the bench is from 1953. Fixing it for friend it came in unmolested abt 5 or 6yrs ago. I took a quick look at it then and after some troubleshooting found what I thought was a bad 1st IF transformer. Fast forward to now. Got it up on the dining room table started to sort it out. Plugged it in and gave it a go. Had audio hiss with some pops and level changes. So went through and replaced the caps in the audio stages. Helped a little and cleaned the controls too.
Applied a 455kc signal to the grid of the IF amp tube and received a signal from the spkr. Did the same to the plate of the mixer tube (1L6) read very expensive toob) All was well. Tried the input grid of the 1L6 and got nothing. Hmmmm. Should be able the pass a signal. Check voltage and look pretty good. Unfortunity my old wartime I-177 tube tester won't test a lot of these modern 7 pin toobs.
Did some research and found that you can use a 1R5 (read cheap battery toob use in just every portable made in the 50's and 60's that don't have a 1L6) with a modification. (remove pin 5 from the tube). Dug a 1R5 and off came pin 5. Carefully inserted in to the set and gave it a try. Well the 1L6 was bad the 1R5 caused it to spring to life.
So now it's working still is albeit noisy but still several bumblebee cap that need to go. Friends job is to come up with a good 1L6!
Ordered a bunch of mylar caps, resistors, and a few micas. So I'm waiting for them to show up to finish this and that Philco 42-854
Terry