[R-390] (no subject)

[Dan Merz]

Bob,  since nobody jumped in on this one - here are my thoughts - I have
experience with wood cabinets only to the extent that I built one for a
communications radio because I thought it would be "cheaper" than finding a
metal cabinet and because I like woodworking.  However,  I abandoned the cabinet
entirely eventually because it looked like it didn't belong.  I converted this
cabinet to another use.   I operated my 390a quite a while without any cabinet
setting on my working table with  1 x 2 boards under each side to raise the
front panel for clearance. The one negative to this was dust that would fall in
on the gear train so I covered that area when not operating the set.  Eventually
I modified a nice metal cabinet to fit it (shortened the depth).  I think if I
were to build a wood cabinet again,  it would be out of  good quality thin
plywood,  not over 3/8,  or possibly 1/2 inch,  and I would paint it gray for a
390a.  1/2 inch may be preferred because I can use biscuit joints with that
thickness.   I'm sure you could take care of the cooling with fans and some
convection holes in the upper sides with the fan taking air across the bottom
where the power supply is - but I haven't given much thought to this,  as the
idea of a wooden cabinet doesn't appeal to me.  I probably haven't helped much
but I don't think it would take took much air movement to cool the radio but
with a wooden cabinet it may be a good idea because of the poor heat conduction
of wood.  The only negative I think of with fans is the amount of dust that gets
hauled in and deposited - I was amazed when I opened my wife's computer after 3
years of service - there was a lot of deposited material everywhere.  Not much
of a filter used I guess.    The metal cabinet I have has an opening of about 2
in. across the front below the 390a front panel and I leave the blank panel
that fits here off to let some air move in across the bottom through to the
back. The upper part of the chassis is only open at the back.   This seems
adequate,  though I rarely leave the set on more than 12 hours at a time when I
use it.    Dan

Benzon Robert wrote:

> Gents:
>
> I am a new proud owner of a decent Motorola R-390A without covers of any
> kind except the sheet aluminum closest to the electronics, and would like to
> construct a wood cabinet for it.  Has anyone out there done this? How much
> space around the aluminum do you folks recommend?  And, what kind of
> forced-air cooling system would be involved?  I am a user of this radio and
> not a technician, but could wire up external biscuit fans, I believe.  This
> wood cabinet would be a tabletop type, to sit on the specially reinforced
> table I had to build for the thing when I got it.  Boy, is it heavy.
> Thanks, in advance, for the advice.
>
>
> Bob Benzon
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