[Hammarlund] Landed on my doorstep

[Todd, KA1KAQ]

On Fri, 18 Mar 2005 07:09:28 -0500, GBrown <gkbrown at gwi.net> wrote:
> Well, a van backed up to my shop, opened the door and unloaded a SP-600JX-1
> with all sorts of manuals. I would give this receiver a 6 on the 10 scale.

Gary - 

Unless you have a load of money involved that you need to recoup, I'd
say restore and use. Other than the main turret, it's fairly easy to
replace bad caps and resistors. Some models had black beauty caps that
will be obviously cracked and leaky, some have ceramic caps (later
models, I don't think the JX-1 does) and need very little. Cosmetic
restoration is fairly simple.

Geartrain should be cleaned and carefully lubed, but you must take
great care not to get too much on the gears or it will find its way
onto the edges of the main dial and mess up the friction drive. If
your tuning slips, clean this up really well (usually takes a few
times) with some alcohol and it should return to normal.

One thing that the SP-600 has a bad reputation for is drifting. My
first one did this and it was very annoying. Then one day Les Locklear
pointed out that the main transformer has multiple taps for different
power input. He suggested I check it and see if it was on 125 or 110v,
and move it to 125 if it was. Sure enough, I made the switch and the
unruly beast settled right down. A 5-10 minute change made it into a
completely different radio.

Other than that, just the usual: a good cleaning, check the tubes and
fuses, remove shiney shields and so on. While very good, the audio is
a bit restricted but not as bad as your typical SSB receiver. I don't
think anything comes close to being as smooth to tune except maybe the
SX-28 or AR88 series. Tuning dial calibration and bandspread leave a
bit to be desired, but it was early 50s technology and, along with the
R-390 receiver, a huge step forward in design.

Also, a 3 wire cord is a good idea and easy to install (as you already
know). I'm sure others will chime in with additional suggestions. Once
you get it restored, you will love it.

73, Todd/'Boomer'  KA1KAQ