Thread: Eddystone 888A.
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Old 14th Dec 2015, 8:46 pm   #99
Wendymott
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Join Date: Jun 2013
Location: Huddersfield, West Yorkshire, UK.
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Default Re: Eddystone 888A.

Hi Al. Ooopppssssss.. Sorry for any confusion I have caused. The problem certainly lies in the Second stage tuning on 15M. The fault appeared to be mis tracking, where setting the L at the LF end, for a signal peak.................. then setting the tuning at the HF end and peaking the Trimmer for "maximum smoke", caused the LF end to require another adjustment of "L" to peak the signal, add infinitum... until I had no adjustments left and still no proper peak.
In my investigations, I removed the Local osc valve V3, and fed in a signal from the spectrum analyser tracking generator, and monitored the grid of the mixer. There is no tuning "hump" at all.
The beehive cap is the only component I have not replaced. Even I am not convinced its to blame, the only other possibility is that the "shorting" contact of the bandswitch is not clearing the contact, and is killing the signal.
I will know later tonight either way... as I can "borrow" a trimmer from another coil, and also check the switch contacts.
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Regards
Wendy G8BZY
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