It could also be a bad xtal filter or poor filter contact, or poor contact
along the receive chain. Clean them all or try jumpering the filter
contacts.
Barry N1EU
On Tue, Oct 6, 2015 at 3:13 AM, Gary - AB9M <glhuber@msn.com> wrote:
> Slide the AUX ANT / AUX RX switch back and forth about 20 times......
> often corrosion / oxidation causes weak receive; cleaning the switch will
> put things back to normal.
>
> 73 & DX,
>
> Gary - AB9M
>
> -----Original Message----- From: jon greenwood via TenTec
> Sent: Monday, October 05, 2015 9:40 PM
> To: tentec@contesting.com
> Cc: jon greenwood
> Subject: [TenTec] Corsair II weak weak receive
>
>
> Hope some of the good troubleshooters on here can point me in a direction.
> I have a Corsair 2 that is very weak on receive. I have checked transistor
> voltages on IF/AF board 80984, the Osc/mixer board 80975, and the RX mixer
> board 80987. All seem good or very close to specs in manual, except Q6 on
> RX mixer 80987.
> I am reading 11.5 volts on base emitter and collector in receive mode. In
> Transmit these all read correctly base emitter and collector zero volts. I
> replaced the 270pf cap C24 as well as C25 5-25pf variable cap. No change. I
> removed the Q6 transistor and the radio receives exactly the same. I
> replaced with a new transistor with no change. So my thought is a bad a
> component around Q6 but at this point I am stumped on what it is. I also
> checked D7 and D8 pulling them off the board and just checking with my ohm
> meter. Flow in only one direction on each so they seem good.
> Any thoughts/ test procedures would be much appreciated. I have a 100mhz
> digital scope and an older Fluke DMM that I have to work with.
> Questions/Thoughts? Jon N8MUS
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