Valiant freq pulling

[Eddy Swynar]

John...

You didn't say if this was BAND SPECIFIC, or on ALL bands...

Some years ago my old Ranger-1 drove me NUTS---on 40-meters ONLY, the actual
on-the-air signal was LOWER than the spotting frequency by some 15-25-KHz!

The reason? The screws on the top of the internal VFO shield assembly needed
tightening...by being EVER so slightly loose, it was enough to allow RF
feedback from subsequent stages BACK into the VFO (no problem, of course,
when spotting because the final PA is dis-abled).

Also, 40-meter frequencies are all "straight through", right from stem to
stern---NO doubling on that band (20, 15, & 10 were OK, as was 80). To this
day I don't know if the problem manifested itself on 160 in the same way
(again, no doubling on that band)---I didn't operate top band at the time...

Anyway, something for you to consider!

~73~ Eddy VE3CUI - VE3XZ




----- Original Message -----
From: "john w. king" <jbkking at BELLSOUTH.NET>
To: <BOATANCHORS at LISTSERV.TEMPE.GOV>
Sent: Sunday, January 06, 2002 10:28 AM
Subject: Valiant freq pulling


> When tuning the exciter control on my Johnson Valiant, the VFO freq moves
> away from Zero and returns as the cap is rotated and returns to original
> zero as cap reaches max tune for exciter. The VFO freq also moves when the
> final amplifier C1 is tuned, moves away and returns to original freq as C1
> is tuned through range. The freq returns to zero at the point of maximum
dip
> when resonance is achieved in the tank circuit.
>
> Sounds to me like a coupling cap between the stages may be shorted and
> preventing the stages from being isolated. What do you think may be
causing
> the interaction between the VFO freq and tuning of subsequent stages?
Thanks
> and 73, John, K5PGW
>
> -----------------------------------------------------------
> This list is a public service of the City of Tempe, Arizona
> -----------------------------------------------------------
>
> Subscription control -
http://www.tempe.gov/lists/control.asp?list=BOATANCHORS
> To post - BOATANCHORS at LISTSERV.TEMPE.GOV
> Archives - http://interactive.tempe.gov/archives/BOATANCHORS.html

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.asp?list=BOATANCHORS
To post - BOATANCHORS at LISTSERV.TEMPE.GOV
Archives - http://interactive.tempe.gov/archives/BOATANCHORS.html