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Old 14th Oct 2019, 8:57 pm   #1
music-centre
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Join Date: Sep 2007
Location: Brentwood, Essex, UK.
Posts: 687
Default Problem with Dynatron RG38 Radio section

Hello All,
Although a Radiogram I am posting this in the Radio section as its only concerned with Radio reception.
I am being really optimistic with this one I know but I wondered if anyone has had a similar fault to this on one of these.

The FM band is fine with excellent reception as are all the AM bands most of the time but using it on MW it will occasionally reduce its gain so that on a fairly weak station the volume is reduced to hardly anything,the volume gradually reduces over a few seconds.

Changing wavebands always brings it back so I thought dirty switch contacts, after cleaning them twice no difference.

I have since found that touching the contacts on the Ferrite rod Aerial with a screwdriver will get it back as well as once just touching the chassis with a screwdriver with me holding the shaft did.

AGC fault perhaps?

I have only changed the output valves grid coupling capacitors.I cant seem to find a manual for it, just wondered if someone has had experience with one of these and could narrow down the area I should be looking- I don't really want to go on a mass capacitor changing exercise if possible.

I have tried swapping the 2 RF/IF valves and cleaned the valveholders, no amount of banging the chassis will produce the fault.
Thanks,
Steve.
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