[R-390] Dead 6MHz and 10MHz

[Barry Hauser]

Roy wrote:

> Yes. The cover has three screws: one at the front visible from the top, 
> and two
> at the rear, not so easy to see. These two at the rear are accessible from 
> the
> back of the radio if you have a LONG phillips screw driver. They are able 
> to
> fall down into the radio and be hard to retreive but with care you can 
> capture
> them as they are loosened.

In my description, I think I was confusing the oven/xtal cover with the 
cover for the mechanical filters.  Yes, screws are on the side for the xtal 
cover only -- not the top .

>
> Note: the cover of the crystal oven has a heater element in it (along with 
> some
> fiberglass insulation). The heater is fed power by two pins that engage
> correstponding contacts in the base of the unit. SO...Pull straight up 
> once the
> cover is loose. Get all three screws out before you remove the cover.  All 
> this
> is easy to see and manage once you've done it once.


Not all of them are "plug 'n play" design -- that much I remember.  Many are 
as Roy describes -- integral contact pins.  Others are hard-wired with a 
pair of leads.  This may be a modification to ensure good connection to the 
heater element in the cover.  Just watch for that as you lift the cover.


> It's ok to run the radio with the crytal oven cover off. You MAY find that 
> just
> removing and replacing the crystal will solve the problem. You should do 
> this
> for all the crystals to make sure they all have nice connections.  More 
> likely,
> the crystal is bad, but let's hope it's just a bad connection.

It's sometimes difficult to get a good connection if the sockets are of the 
"cost reduced" type I described.  You might notice that the crystals are 
rather wobbly and there's hardly any tension on the pins when your remove or 
insert them.  If so, then try staking them if they are of the type I 
described.  They look like dimpled plated stampings with pinholes and two or 
maybe 4 cuts in the metal radiating out from the holes for the pins. Staking 
them closes up the pin holes a bit - enough to dig into the pins and make a 
better connection.  Don' t do it unless there's clearly a lot of slop.

They may be of a better design, more like a conventional crystal socket --  
The above does  not apply to that type.

Barry