12-13-2017, 03:19 PM
Hi guys,
Its been quite a while since I've posted anything here. Between getting Mom settled in the nursing home and selling her house and catching up on stuff that got put on hold while taking care of her, I haven't had much time to work on radios.
Well I'm restoring the radio in my 1948 Plymouth, thought it would be a fun project now that winter is coming. I've recapped the whole radio and replaced most of the resistors and I've installed a new solid state vibrator and replaced the missing speaker with a modern equivalent.
Here are the problems I'm having,
When hooked up to a fully charged 6V. battery (positive ground) and turned on, I immediately get a loud buzzing from the speaker, the tone of the buzz does change a bit as the set warms up but does not go away. I can also vary the tone slightly by rotating the tone control, but no stations are heard. I get static and clicks when touching my meter leads to tube pins, so I'm guessing the amp section is working. I tried hooking up my signal generator and I did hear a faint tone at one point. I was able to vary the loudness slightly by tweaking the IF transformers.
Also my B+ voltages are about 30 volts lower than the schematic lists. As I said I have replaced all the caps including the electrolytics using the same values.
I've just started troubleshooting and I ordered a Sams Photofact for it as the one on Nostalgiaair is kind of confusing to me and hard to read.
I'm not very familiar with old car radios so if anyone out there has any ideas or tips on what I should be looking at, I would GREATLY appreciate it! Thanks!!!!
Kevin
Its been quite a while since I've posted anything here. Between getting Mom settled in the nursing home and selling her house and catching up on stuff that got put on hold while taking care of her, I haven't had much time to work on radios.
Well I'm restoring the radio in my 1948 Plymouth, thought it would be a fun project now that winter is coming. I've recapped the whole radio and replaced most of the resistors and I've installed a new solid state vibrator and replaced the missing speaker with a modern equivalent.
Here are the problems I'm having,
When hooked up to a fully charged 6V. battery (positive ground) and turned on, I immediately get a loud buzzing from the speaker, the tone of the buzz does change a bit as the set warms up but does not go away. I can also vary the tone slightly by rotating the tone control, but no stations are heard. I get static and clicks when touching my meter leads to tube pins, so I'm guessing the amp section is working. I tried hooking up my signal generator and I did hear a faint tone at one point. I was able to vary the loudness slightly by tweaking the IF transformers.
Also my B+ voltages are about 30 volts lower than the schematic lists. As I said I have replaced all the caps including the electrolytics using the same values.
I've just started troubleshooting and I ordered a Sams Photofact for it as the one on Nostalgiaair is kind of confusing to me and hard to read.
I'm not very familiar with old car radios so if anyone out there has any ideas or tips on what I should be looking at, I would GREATLY appreciate it! Thanks!!!!
Kevin
