[R-390] A vs non A

[Richard Loken]

On Tue, 9 Oct 2012, Robert Newberry wrote:

> I may be picking up up what I believe to be a R390. When I was talking to a
> friend about this he kinda scoffed saying they were less desirable and
> harder to work on than the 390A.

I hardly think so.  There are fewer examples of the R-390/URR so there is
less documentation, fewer parts, and less community knowledge to be had but
it is just as understandable and repairable as the A version.

You will have fewer problems with bad capacitors and no aging mechanical
filters to worry about but you will have a series regulator with its
associated heat problems to occupy your spare moments.

There are a many similarities of design and contstruction but few parts
are interchageable.  All of the similarities, differances, problems, and
solutions are well documented inspite of the above comment about the
reduced availability of documentation.

-- 
   Richard Loken VE6BSV, Unix System Administrator : "Anybody can be a father
   Athabasca University                            :  but you have to earn
   Athabasca, Alberta Canada                       :  the title of 'daddy'"
   ** richardlo at admin.athabascau.ca **             :  - Lynn Johnston