1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Other Radios (Non-Philco)
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Linear Mode
RCA. 120 tunning too narrow and distortion
MrFixr55
Phorum Expert
*****
Posts: 1,083
Threads: 9
Joined: Jul 2020
City: Greenlawn State, Province, Country: NY
#2

12-09-2024, 02:35 AM
Hi Bruce,

Looking at the schematic, check cathode bias resistors R3 (RF, IF) and R7 (1st Detector). Also check R9 (B+ to oscillator.

Depending on where you injected the audio signal, good volume and tone from an injected signal rules out the 1st Audio and Output circuits. Changes in distortion, signal drift and changes in tunability indicate issues in the RF, IF and 1st Detector circuits. Maybe shotgun the resistors. Even though the caps looked like newer Aerovox units, replacing paper caps with mylar is still prudent, as paper caps will still break down.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55
Find
« Next Oldest | Next Newest »


Messages In This Thread
RE: RCA. 120 tunning too narrow and distortion - by MrFixr55 - 12-09-2024, 02:35 AM



Users browsing this thread: 6 Guest(s)
[-]
Recent Posts
Were there other kinds of capacitors in 1934 other than the old Wax Paper Capac...
OK, Interesting, I didn't realize these were used by other companies as well, I've only seen this style of caps in one o...captainclock1988 — 11:05 PM
Westinghouse H104
From the schematic, I think that the 2 6Y6s in this set are in parallel, not push-pull. Look at the output transformer....MrFixr55 — 10:41 PM
Philco 46-480 Electronic Restoration
Let me see how much I can enlarge them. I had formatted this to plot on an E sized paper, but I do realize that the bloc...jrblasde — 10:36 PM
Predicta parts
"Hello, good afternoon, does anyone have the antenna, the top cover of the tuner and all the knobs from a '58 Philc...GarySP — 10:18 PM
Need Help Identifying an Old Zenith Radio Model I used to Have when I was a kid
There are many common reasons for a radio to not play but the phono section to work.  For a transformer powered set, any...MrFixr55 — 10:12 PM
Philco 46-480 Electronic Restoration
A suggestion: increase sizes of yuor passives. They are not well-readable. Lool at the right upper part of the section ...morzh — 10:09 PM
Were there other kinds of capacitors in 1934 other than the old Wax Paper Capac...
Hi Captain Clock, RCA used caps like these in some of their radios. I have 2 RCA Farm sets ca 1936 that used caps l...MrFixr55 — 09:40 PM
Philco 46-480 Electronic Restoration
Hi Joseph, I understand that you want to get all of the bugs out of the schematic before printing the last version. ...MrFixr55 — 09:27 PM
Were there other kinds of capacitors in 1934 other than the old Wax Paper Capaci...
Hello everyone, I was replacing the original capacitors from my 1934 Stewart-Warner Tombstone Radio the other day and I ...captainclock1988 — 09:08 PM
Philco 60 restoration
All nice looking.  Arran, the GE from 1933 may be the GE version of the RCA R-28-P "Radiolette", especially if...MrFixr55 — 07:56 PM

[-]
Who's Online
There are currently 2814 online users. [Complete List]
» 2 Member(s) | 2812 Guest(s)
AvatarAvatar

>
  1. The PHILCO Phorum
  2. Various and Sundry Categories
  3. Other Radios (Non-Philco)