Re: Assembly manual Rev 1.08
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Hi Des?
Yes I think it is possible. If the I-Q pot has to compensate for usual amplitude imbalances but additionally has the trauma of having to deal with the additional imbalance caused by the R19/R25 reversal then it could run out of trimmer adjustment range. I think it's quite possible.?
Still, if your unwanted sideband is already excellent I think I'd be inclined to leave it as is!
73 Hans G0UPL? ?
On Dec 9, 2017 1:56 PM, "QRP_nut" < raspiham1973@...> wrote: Hi Hans and thanks for swift the reply,
Would R19 & R25 being reversed on the PCB possibly cause one of the I/Q trim-pots to run out of adjustment while setting-up the I/Q balance? I just checked my QCX80 and R19 & R25 are reversed.
While setting-up the I/Q balance I found one of the two pots' (dont remember which one but probably R27) ran out of adjustment and became "one ended" though image rejection by this time was allready excellent so I left it as it was.
But looking at the schematic again in light of the revalation regarding R19 & R25 it would seem that those two resistors being reversed in position might account for one of the adjustment pots being at the end of its adjustment range?
73,s
Des (M0AYF)
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