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I have a mid-era Hammarlund HQ-129-x. It sounds great if I don't count the motorboating. But the problem is in the middle bands. I got the radio way out of alignment, and managed (I think) to get the IF working.

I receive strong stations (folded, loaded, irregular-dipole) okay, no images. Even the blasting AM station on 1450 sounds great, so long as I throttle way back on the sensitivity control. I only hear it on 1450, so the selectivity is good. No images!

But the weirdest part is: I get WWV interference across the bands, all six, but it's the middle four that gets it the most. I can pick up the WWV signal when it's clear, and it interferes with itself. I could understand if 1450 were the noisy cricket, but... WWV?

How can I snuff out WWV from wherever it's not supposed to be?

Caoimhin

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    $\begingroup$ What do you mean by "I can pick up the WWV signal when it's clear, and it interferes with itself." When what's clear? And what does "interferes with itself" mean specifically? $\endgroup$
    – Phil Frost - W8II
    Dec 28, 2020 at 4:43
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    $\begingroup$ You will need a RF signal generator (50 kHz to 20 MHz) to find unwanted spurious reception spots of your receiver. Something must be wrong in the input circuit of your receiver. Or do you live within a few miles from the WWV transmitter? $\endgroup$
    – user16925
    Dec 28, 2020 at 18:03
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    $\begingroup$ Hello and welcome to ham.stackexchange.com! $\endgroup$
    – rclocher3
    Dec 28, 2020 at 22:59
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    $\begingroup$ When conditions are right, I can hear the WWV clearly, and as the ionosphere fluctuates, WWV is heard, but with a serious buzz. I can sometimes hear this on the WWV signal, and the station itself can't be heard. No dial change. I'm in Rhode Island, a few time zones away from Colorado. I live just a few miles away from a full power AM station. I only hear the AM station on its true dial position, and I have to throttle back all the way on the sensitivity control and it will sound great, save for motorboat. $\endgroup$
    – Caoimhin
    Dec 30, 2020 at 2:11
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    $\begingroup$ Antenna type: folded, random-loaded asymmetrical dipole apartment-type antenna, connected on the A terminals. Grounding the case, there's a few volts AC to the screw terminal on the house plug. It has no apparent effect, but ground-effect goes away when I put a 0.1uF cap in the wire to ground. I did play with the alignment again, and don't know what I did right, but the WWV interference is gone. The signal generator will improve things. I should de-tweak to bring back the WWV just to see what I did right! $\endgroup$
    – Caoimhin
    Jan 4, 2021 at 14:27

1 Answer 1

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If you were messing with the alignment, it's possible that you have inadvertently switched the local oscillator from high side to low side injection. Or vice versa. Hence all the unwanted images. Rule number one for boat anchors (from personal experience) is "don't mess with the alignment." Unless you know what you're doing, chances are things will get worse. At this point, make sure you have a proper service manual for the radio and that you go through the entire procedure to the letter.

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