[Milsurplus] FRR-59 vs R-390A

[Randy Zelick]

Hello lists,

So I have some familiarity with both sets, but not numbers. Here is some 
general info for the thread...

As you might expect, there are plus and minus factors for both sets, and 
what you want to do with them can determine which is better.

                         FRR-59                    R-390A
Stability               excellent                 adequate
Sensitivity             very good                 very good
Serviceability          OK(1,2,3)                 excellent
Ease of use             more knobs to adjust      fewer knobs to adjust
Sound quality           better                     OK
selectivity             OK                        excellent 
SSB detection           excellent                 poor(4)
rate of SSB tuning      excellent                 poor
size, weight            outrageous(5)             serious
reliability             OK(5)                     excellent

(1) The FRR-59 is modular, but not to the same extent as the R-390. Many 
modules require unsoldering wires to remove.
 
(2) Part of the advantage of the R-390 has to do with how popular and
common it is. Lots of expertise and parts kicking around.

(3) The FRR-59 has one serviceability edge -- slide out and hinged drawers
make it very easy to get at test points, pull tubes, etc. A rotating slide
mechanism *could* be installed on a R-390, but it is not often done.

(4) Of course many adapters are possible, which improves the situation. On
the other hand, the FRR-59 has ISB detection. One very cool thing to do is
ISB detect AM broadcast signals.

(5) A major flaw in the FRR-59 design is that the set is too heavy for its
cabinetry design. Any rough handling and many little pawls, cams, shafts,
couplings and so forth can be bent.

(6) With around 60 tubes and a more complex circuit, the FRR-59 has more
stuff to go bad. One the other hand, the manual is much better than the
R390A manual(s). Also, the FRR-59 uses just a few *types* of tubes, so it
is easy to have necessary spares and sub them out.

There are some other quirks (features??) of the FRR-59 that deserve 
mention:

a) There is a thermostatically-controlled fan. Great when it is not 
running.

b) When you switch to SSB detection, the filament string in the AM 
detector section goes out, and vice-versa! So you just have to wait for 
the newly switched-in section to warm up.

c) There is an elaborate cord-reel system and "blister" system to keep
power and signals routed around between cabinet sections, and when you
pull out drawers. If the cabinetry gets tweaked (easy to do), the
connectors don't mate or seat correctly leading to minor pyrotechnical 
displays. Fixing this sort of damage is squarely in the "un-fun" category.

d) If you get a submarine version of the FRR-59 it has very cool orange 
lights.

e) The tuning mechanism on the FRR-59 is quite elaborate and beautifully
built, yet has plenty of backlash. Surprising? Well the tuning rate is so
slow it does not matter. You just stroll through SSB signals. The downside
is that it can take a while to move certain frequency distances.

OK, so there is some material for you!

Cheers,

=Randy=

 -- 
R. Zelick				email: zelickr@pdx.edu
Department of Biology			voice: 503-725-3086
Portland State University		fax:   503-725-3888

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