Weirdness with 396T/Satellit 800 interaction

KB2GOM

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Not long ago, I stripped out almost all of the trunked systems on my Uniden 396T (leaving only one, NY state Thruway) and programmed two "conventional" channels: (1) nationwide military air frequencies and (2) military SAR frequencies. I got both of those lists from RR.

Now, here's the weird part, if I am scanning the nationwide military air frequencies and turn on my Satellite 800 hf receiver, the 396T locks up on something called "USAFComm," which is apparently 300.6.

If I cycle through the band selector on the Satellit 800, the scanner sometimes releases and goes back to scanning, but eventually it will lock up on USAFComm again. I tried the same thing with my CCrane Skywave SSB, but it causes no reaction in the 396T.

My guess is that the Satellit 800 generates some internal frequency that the 396T detects.
 
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a417

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Not long ago, I stripped out almost all of the trunked systems on my Uniden 396T (leaving only one, NY state Thruway) and programmed two "conventional" channels: (1) nationwide military air frequencies and (2) military SAR frequencies. I got both of those lists from RR.

Now, here's the weird part, if I am scanning the nationwide military air frequencies and turn on my Satellite 800 hf receiver, the 396T locks up on something called "USAFComm," which is apparently 300.6.

If I cycle through the band selector on the Satellit 800, the scanner sometimes releases and goes back to scanning, but eventually it will lock up on USAFComm again. I tried the same thing with my CCrane Skywave SSB, but it causes no reaction in the 396T.

My guess is that the Satellit 800 generates some internal frequency that the 396T detects.
do they share an antenna?
 

ka3jjz

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At that distance they really shouldn't interact, but it sounds like one local oscillator is mixing with the other. If you turn the 800 off does 300.6 disappear? Mike
 

ka3jjz

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Then you have your answer. Do they share a common power supply? It might also be a case of the power cord for the 800 doing the radiating.

It can be a bit tricky to find interactions like this because it could be more than one culprit. Mike
 

majoco

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I have the same effect on 120.6MHz in the aircraft band on a Uniden UBCT8 with a birdie from my JRC NRD515 on 13.261Mhz so I just choose another HF receiver.
 

a417

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Yes. The 396T "unlocks" and goes back to normal scanning.
Have you tried walking around the house with the 396T to see how close your interference field is? Maybe a remote antenna can help.
 

ka3jjz

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The problem with that theory is that it might not be the antenna that is picking up the oscillator(s).

This is a tricky problem to solve, as I said before, because it's not out of the range of possibility that more than 1 culprit is at fault here

Mike
 

wtp

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my 396T used to lock up when my 396XT was on any voice frequency on our old 800 analog system.
since the county moved to 700 i have deleted the frequency, i think it was in the 279 area.
 
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