G3OZF wrote:
Can anyone help with a problem I have with my VL1000 Quadra ?
On 80 metres (on one of the two antennas) and on 160 metres I find the
main fans which start up normally on transmit, only run at slow (and
fluctuating) speed. Has anyone had this problem, and what is the fix ?
SWR is very low on the antennas, and the is no evident issue with
closeness of the antennas, as one is over 200 feet away.
Not only have I found the fans slow down when RF is getting back into
the amp from somewhere, but the 48 VDC supply for the FETs loves to kick
back to 36 VDC.
I haven't had the VP1000 open yet, but from the unshielded cables between
the two & rather the rather meager anti-RF measures inside the VL1000, I'm
not surprised at this happening when the antennas are so close to the shack
as they are in the two locations I've used this amplifier.
You might not be in your own near field, but it wouldn't be surprising to
find that your VL1000 is getting a whiff of RF from somewhere.
73, VR2BrettGraham
--
FAQ on WWW: http://www.qsl.net/k7on/yaesu.html
Submissions: yaesu@contesting.com
Administrative requests: yaesu-REQUEST@contesting.com
Problems: owner-yaesu@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|