My friend asked him to help him with Allwave 23

[Scott Petersen]

Hi,

This is my first post. My friend just bought an Allwave 23, it arrived without receiving any Rf at all, just the Audio was working, I was going to recap it, but someone already restuffrd all of the paper caps in the unit already. I found the coil disk was not tightened all of the way, and then I was able to receive some stations on everything except the broadcast band, I dug a little deeper

and found the mica cap on that coil was shorted by a wire touching it, I moved the wire and was able to pick up the strongest station, buried in noise.

The receiver picks up something on all bands, but there is so much noise it is hard to listen to.

I wanted to align it, (the manual says to make sure the selectivity caps are aligned,and set screws are tight) but upon opening the square covers under the IF's,I saw that two of the small capacitors are opposite the other two, Is this correct, I cannot find a clear picture of the proper orientation.

Thanks,

Scott

[Scott Petersen]

I measured a little over 40 ohms on that one. The tuning frequency matches the dial pretty well also.

[Norman S Braithwaite]

Were you able to align the RF AGC diode as previously described?

Norman 

[Scott Petersen]

It seemed to drop the level of a strong station when I adjusted it. Does that also work on the other bands as well?

IIRC I adjusted it on the broadcast band.

[Norman S Braithwaite]

In theory the RF diode adjustment may be made on any band but it is unlikely that a signal strong enough to align the RF diode will be available on the shortwave bands.  If the RF diode was able to reduce the signal on a strong broadcast station, it is working and aligned (well aligned if the selectivity-fidelity control was full CCW).  It appears clear from shortwave reception that there is not a problem with the RF and IF circuits and the common problem of an open antenna coil has been eliminated therefore the problem is limited to the band switch or BCB components.  The band switch is comprised of three separate switches, the coil wheel, the antenna switch primary located immediately behind the front apron of the chassis, and the antenna switch secondary located in front of the BCB antenna coil in the very center coil shield.  If these switches are all clean and making good contact, then the problem must be a bad component or component wiring.  If the broadcast band stations appear at the correct locations on the dial, the oscillator coil secondary is good and the oscillator is operating but perhaps not at full strength.  Have you checked the oscillator coil primary on the coil wheel?  Another possibility is leakage in the oscillator trimmer or padder.  Both are unusual problems.

Norman

[Scott Petersen]

It'll take me a little while to get back into the radio, to check further.

I'll let you know what happens.