04-05-2011, 02:44 PM
As others have said, it is possible, but better results are had with a signal generator and a meter monitoring the AVC voltage.
Your radio is deaf on the lower part of the dial due to the tracking being off. Typically this is due to the IF being tuned to the wrong frequency. Most IF cans will happily peak anywhere from about 400 to 500KHz. Unless the IF is set to what the radio needs (typically 455KHz) the sensitivity will suffer on the lower part of the dial. Some sets allow adjustments than can peak the lower and upper parts of the dial, but then the middle of the band will be deaf if the IF is not 455KHz.
By ear, you can try to correct the IF frequency. This is done by tuning to a weak station at the bottom of the band, under 600KHz if possible. Now you have to "walk" the IF peak, and the tuning dial in steps for best reception. Try tuning below the station until you just hear it, then peak the IF. If reception improves, walk it lower and try again. If reception is worse, walk it higher and try again. You will reach a point of best reception with the IF peaked after a few steps. If you go too far, the reception will get worse again. Walking the tuning and IF for best reception retunes the IF frequency closer to 455KHz. The process is much faster and more exact with a signal generator. If you have a meter, watch the AVC voltage as it is easier to see the change than hear it.
Once the IF is tuned, then go to a station around 1400Khz and adjust the antenna trimmer capacitor for best reception. Now note the frequency of the station on the dial. If it is not what the station frequency really is, then adjust the oscillator trimmer as you walk the dial to the correct reading. After the dial reads correctly, repeak the antenna trimmer. These trimmers are typically on the tuning capacitor on an AA5 set.
Now check out the set across the dial, hopefully it tracks well now and receives well up and down the dial.
The shortwave section often has a antenna padder or coil to adjust for the bottom of the dial, and a trimmer for the upper part, as well as for the oscillator. I would not adjust the oscillator settings until you get a signal generator as it is rather easy to fubar the alignment and end up with no reception on shortwave.
Your radio is deaf on the lower part of the dial due to the tracking being off. Typically this is due to the IF being tuned to the wrong frequency. Most IF cans will happily peak anywhere from about 400 to 500KHz. Unless the IF is set to what the radio needs (typically 455KHz) the sensitivity will suffer on the lower part of the dial. Some sets allow adjustments than can peak the lower and upper parts of the dial, but then the middle of the band will be deaf if the IF is not 455KHz.
By ear, you can try to correct the IF frequency. This is done by tuning to a weak station at the bottom of the band, under 600KHz if possible. Now you have to "walk" the IF peak, and the tuning dial in steps for best reception. Try tuning below the station until you just hear it, then peak the IF. If reception improves, walk it lower and try again. If reception is worse, walk it higher and try again. You will reach a point of best reception with the IF peaked after a few steps. If you go too far, the reception will get worse again. Walking the tuning and IF for best reception retunes the IF frequency closer to 455KHz. The process is much faster and more exact with a signal generator. If you have a meter, watch the AVC voltage as it is easier to see the change than hear it.
Once the IF is tuned, then go to a station around 1400Khz and adjust the antenna trimmer capacitor for best reception. Now note the frequency of the station on the dial. If it is not what the station frequency really is, then adjust the oscillator trimmer as you walk the dial to the correct reading. After the dial reads correctly, repeak the antenna trimmer. These trimmers are typically on the tuning capacitor on an AA5 set.
Now check out the set across the dial, hopefully it tracks well now and receives well up and down the dial.
The shortwave section often has a antenna padder or coil to adjust for the bottom of the dial, and a trimmer for the upper part, as well as for the oscillator. I would not adjust the oscillator settings until you get a signal generator as it is rather easy to fubar the alignment and end up with no reception on shortwave.
