I am having MAJOR, MAJOR problems with this radio. First of all, it doesn't receive anything. Second of all, the audio comes out very weak.

As far the receiving part, I am unable to get the radio to pick up anything, and an antenna seems to make no difference. All the tubes seem fine, and so do all of the other components. I did notice that the wire connecting the longwire and BNC ports to the K101 relay was broken, and the longwire post was bypassed and the broken wire spliced to the BNC connector.
The audio has constantly been giving me problems. It's very weak even at the maximum. However, when I turn the BFO on, the volume seems to start acting normally.

I do have a technical repair manual which I have looked over again and again, and I have checked EVERYTHING in the radio.

There are also a few less significant issues with this thing:

The "DIAL ZERO" knob is hopelessly jammed and won't budge
The "DIAL LOCK" switch and mechanism is missing
The "BAND WIDTH" control doesn't seem to do anything
The middle section of the Oldham coupler that connects the kHz control knob to the VFO controller is missing. The ends have been pressed together so they move together again.
The "DIAL DIM" switch isn't working right; the light is only off or on.
The two audio ports were removed and replaced with a single RCA-mono headphone jack.

I got this secondhand on eBay. Whoever had it last didn't seem to know what they were doing with it, and really messed it up. Is this radio even repairable?

Keep in mind that this is the first time I have ever dealt with a vacuum-tube radio, so my knowldege about these things is VERY limited at best.

:I am having MAJOR, MAJOR problems with this radio. First of all, it doesn't receive anything. Second of all, the audio comes out very weak.
:
:As far the receiving part, I am unable to get the radio to pick up anything, and an antenna seems to make no difference. All the tubes seem fine, and so do all of the other components. I did notice that the wire connecting the longwire and BNC ports to the K101 relay was broken, and the longwire post was bypassed and the broken wire spliced to the BNC connector.
:The audio has constantly been giving me problems. It's very weak even at the maximum. However, when I turn the BFO on, the volume seems to start acting normally.
:
:I do have a technical repair manual which I have looked over again and again, and I have checked EVERYTHING in the radio.
:
:There are also a few less significant issues with this thing:
:
:The "DIAL ZERO" knob is hopelessly jammed and won't budge
:The "DIAL LOCK" switch and mechanism is missing
:The "BAND WIDTH" control doesn't seem to do anything
:The middle section of the Oldham coupler that connects the kHz control knob to the VFO controller is missing. The ends have been pressed together so they move together again.
:The "DIAL DIM" switch isn't working right; the light is only off or on.
:The two audio ports were removed and replaced with a single RCA-mono headphone jack.
:
:I got this secondhand on eBay. Whoever had it last didn't seem to know what they were doing with it, and really messed it up. Is this radio even repairable?
:
:Keep in mind that this is the first time I have ever dealt with a vacuum-tube radio, so my knowldege about these things is VERY limited at best.

Michael:
I don't think I have ever heard of a Dubrow radio before, so we will need a schematic before much troubleshooting can be done. The first thing I would do is put some WD-40 or some other penetrant in the jammed "Dial Zero" control and try to get it moving freely. We can worry about things like the band width and the VFO after we get it working. Having the audio working at all is a good sign, not having sparks and fire, alos not having to call the fire department to put the house out is an excellent sign.
Things will be a lot brighter when we have a schematic.
Lewis

:

:Michael:
:I don't think I have ever heard of a Dubrow radio before, so we will need a schematic before much troubleshooting can be done. The first thing I would do is put some WD-40 or some other penetrant in the jammed "Dial Zero" control and try to get it moving freely. We can worry about things like the band width and the VFO after we get it working. Having the audio working at all is a good sign, not having sparks and fire, alos not having to call the fire department to put the house out is an excellent sign.
:Things will be a lot brighter when we have a schematic.
:Lewis
:
::
:
:
I hadn't either until I came across this thing.
The schematics for this thing are fairly long, and cover dozens of pages. Since I am new to this site, how do I go about posting them? The manual I have is a PDF copy of the Technical Manual from http://bama.edebris.com/manuals/military/r392/

::Michael:
::I don't think I have ever heard of a Dubrow radio before, so we will need a schematic before much troubleshooting can be done. The first thing I would do is put some WD-40 or some other penetrant in the jammed "Dial Zero" control and try to get it moving freely. We can worry about things like the band width and the VFO after we get it working. Having the audio working at all is a good sign, not having sparks and fire, alos not having to call the fire department to put the house out is an excellent sign.
::Things will be a lot brighter when we have a schematic.
::Lewis
::
:::
::
::
:I hadn't either until I came across this thing.
:The schematics for this thing are fairly long, and cover dozens of pages. Since I am new to this site, how do I go about posting them? The manual I have is a PDF copy of the Technical Manual from http://bama.edebris.com/manuals/military/r392/

Hookay!
I have ppulled my head back into the sunshine, it was the Dubrow name that threw me. This radio was made by a number of companies, so finding parts and stuff should be pretty easy. No matter how complex, it is just a radio with extra stuff added on. I'll study the schematic, and add my thoughts when I do.
Lewis
:

Michael

You sure picked a hard receiver for a start. R392 is similar to the R390 but operates on low voltage, in a jeep. Do you have a good, steady, 28 volt supply.

There are internet sites which specialize in the R392. If you can't get information contact groups using R390/A receivers.

Norm

:I am having MAJOR, MAJOR problems with this radio. First of all, it doesn't receive anything. Second of all, the audio comes out very weak.
:
:As far the receiving part, I am unable to get the radio to pick up anything, and an antenna seems to make no difference. All the tubes seem fine, and so do all of the other components. I did notice that the wire connecting the longwire and BNC ports to the K101 relay was broken, and the longwire post was bypassed and the broken wire spliced to the BNC connector.
:The audio has constantly been giving me problems. It's very weak even at the maximum. However, when I turn the BFO on, the volume seems to start acting normally.
:
:I do have a technical repair manual which I have looked over again and again, and I have checked EVERYTHING in the radio.
:
:There are also a few less significant issues with this thing:
:
:The "DIAL ZERO" knob is hopelessly jammed and won't budge
:The "DIAL LOCK" switch and mechanism is missing
:The "BAND WIDTH" control doesn't seem to do anything
:The middle section of the Oldham coupler that connects the kHz control knob to the VFO controller is missing. The ends have been pressed together so they move together again.
:The "DIAL DIM" switch isn't working right; the light is only off or on.
:The two audio ports were removed and replaced with a single RCA-mono headphone jack.
:
:I got this secondhand on eBay. Whoever had it last didn't seem to know what they were doing with it, and really messed it up. Is this radio even repairable?
:
:Keep in mind that this is the first time I have ever dealt with a vacuum-tube radio, so my knowldege about these things is VERY limited at best.
:

I have been using a 24 VDC power supply, which, according to specs, should work. I'll try poking around some more online to see what I can come up with.

If memory serves me, this equipment has 600 Ohm audio output. One would need a line to voice coil matching transformer to use with a low Z speaker...

Clifton

:I have been using a 24 VDC power supply, which, according to specs, should work. I'll try poking around some more online to see what I can come up with.
:

:If memory serves me, this equipment has 600 Ohm audio output. One would need a line to voice coil matching transformer to use with a low Z speaker...
:
:Clifton
I have been using 600 Ohm headphones. I replaced the tubes today, and, not surprisingly, nothing really changed. The background hiss seems slightly louder and the meter moves when I adjust the squelch level, but there is no static. This also doesn't seem to change with the BFO on.