[Hammarlund] Hello, from Japan, Re: Hammarlund Digest, Vol 176, Issue 1

[Katsuhiko Hirai]

Dear Bill, KC0INQ OM,

 Hi, good evening and good morning from Nara, middle west in Japan.
It's now 11:27AM in JST, of Sunday, here.
I'm a retired business person tentatively for taking care of my mother
in a bed.
I appreciated your trial story to rebuild a lovely SP-600 receiver.
Almost two decades ago, I have an experience to recap all BBs 
in a chassis of receiver and make tuning dial smoothly, so-called 'Silky touch'.
After correcting it, I could enjoy listening SWL and BCL activities for
a while.
Unfortunately, but he is now sleeping in a box that I put it when I
moved to return to my home town for caring my mother, more than ten
years. 
I have to appreciate you, because your posting made me remember my
lovely SP-600-JX1 receiver.
If you have any troubles into rebuilding, let me know.
I hope you enjoy to complete your project.

Best regards,
Katsuhiko Hirai
JA3ECA, exN8EYH/Dayton OH
-- 
Katsuhiko Hirai <mxc04040 at nifty.ne.jp>
in Ikoma, Nara, Japan. 
P.E. of Information Technology,  
Researcher of the Software Process Engineering, 
Amateur Radio Operator: JA3ECA.

On Sat, 12 Sep 2020 14:32:53 -0400
hammarlund-request at mailman.qth.net wrote:

> Date: Sat, 12 Sep 2020 12:30:09 -0500
> From: "William Radmer" <bradmer at comcast.net>
> To: <hammarlund at mailman.qth.net>
> Subject: [Hammarlund] Rebuilding a derelict SP-600 receiver
> Message-ID: <0b8c01d6892a$5db345f0$1919d1d0$@net>
> Content-Type: text/plain;	charset="us-ascii"
> 
> Greetings,
> 
>  
> 
> This is my first post after joining the group a few weeks ago. I am
> rebuilding an SP-600 R-274C  purchased several years ago from the brother of
> a silent key. It must have been stored for years in his unheated garage (I
> live in MN) and was very dirty with light corrosion on all the metal
> surfaces. It was missing the audio output transformer, several tubes and a
> few knobs, but hadn't been modified to any extent. I have been collecting
> the missing bits for a while, so on a hot day in July I decided to pull it
> off the shelf and see if it could be put the receiver back into working
> condition. I've been working on tube radios for a while, but this is the
> first rebuild I've attempted of a radio of this size and complexity. After
> reading about all the problems with leaky capacitors in these units (it was
> full of the infamous "Bumble Bees of Death") it was clear all the molded
> paper caps and electrolytics were the first thing that had to go. As those
> of you who have attempted a full recap of a Hammarlund know, this requires
> dismantling many parts of the radio to gain access to all the bad caps, the
> RF section requiring the most effort to remove for service. After
> dismantling the right side of the radio and carefully pulling the RF section
> I found a previous "repair" had bent a number of the contact fingers which
> connect to the band coils when you change bands. Luckily, only two of the
> contact pairs had broken on one side, with a passable connection left on the
> remaining contact. After the RF unit was recapped and repaired all the caps
> were replaced systematically in the other parts of the receiver.
> 
>  
> 
> At this point, the rebuild is almost done! 72 capacitors have now been
> replaced along with the power cord and wrongly sized fuses, a replacement
> audio transformer has been installed and the RF unit will soon be wired back
> in place. I plan on checking resistances on all the tube socket pins prior
> to bringing AC power up slowly on a variac  while checking the B+ voltage.
> If no other problems come to light,  full alignment of the receiver will
> finish up the rebuild. When I got the receiver it was missing the bottom
> cover for the band coil turret and I'd like to replace it if anyone has a
> cover for sale or knows where I can buy a replacement cover.
> 
>  
> 
> I am excited to get this excellent receiver working again after being
> neglected for so long and left for dead. Let me know if you see any issues
> with the rebuild or if you have tips or advise you can share to make it
> better.
> 
>  
> 
> Regards,
> 
>  
> 
> Bill Radmer
> 
> KC0INQ
> 
>