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THE AM BULLETIN BOARD => Technical Forum => Topic started by: k6hsg on April 03, 2021, 10:40:45 AM



Title: Hammarlund SP-100X
Post by: k6hsg on April 03, 2021, 10:40:45 AM
I have a Hammarlund SP-100X That I bought probably 20 years ago when I lived near Springfield Missouri.  It is serial 2935.  At the time I powered it up and it worked sort of for a short while.  Then one of the screen capacitors shorted and let the smoke out of the resister.  I started replacing the capacitor inards and then let the project slide until today.
I have been following this post with interest and decided that it is time to get it working. 
It appears to be as built except for the first audio transformer. 
  I have two other Super Pro's.  Serial 3255 which has the SP-200 front panel, Sprague 600 line Tubular Condensers and the 100 glass tubes.  The serial is the SP-100 range but looks like a 200.  it has the correct audio transformer so I will probably use it.  It also has an incorrect square meter.
  The other 200 is a late, built during the war, receiver serial 16116.  It looks pretty original and I will probably keep it as is.I currently live in Picture Rocks, Arizona near Tucson.
I would appreciate any and all comments




Title: Re: Hammarlund SP-100X
Post by: k6hsg on April 03, 2021, 10:43:09 AM
I didn't do well on the pictures .
going to try again


Title: Re: Hammarlund SP-100X
Post by: Scott SWL on April 03, 2021, 11:14:28 AM
Your faceplate looks in nice shape compared to my SP-10, 200(BC779), and 400.
It's interesting to see the evolution from the SP-10 to the SP-200, as I see elements of both in your unit. The tag boards are not in my SP-200, and there are no octal tubes in my SP-10 originally (someone "upgraded it" to the SP-100 audio section sometime in it's history, but retained the original transformers.
My SP-10 is a basket case waiting on parts from W7TFO and the SP-200 has a broken slide in the band switch, also waiting on parts. they have chrome chassis.
The 400 is stock, except for the knobs.
Schematics and alignment info on Page 214
of TM-11-310
https://www.dropbox.com/s/z4ihkakyw512ujq/214%20TM-11-310-SCHEM.PDF?dl=1


Title: Re: Hammarlund SP-100X
Post by: k6hsg on April 03, 2021, 03:16:38 PM
Thank You Scott
That's a handy manual
John


Title: Re: Hammarlund SP-100X
Post by: k6hsg on April 03, 2021, 08:18:25 PM
After further investigation the serial 3255 is an SP-100X.
My error.  3255 has Cornell Doubler Tiger Capacitors. 2935 has the Sprague capacitors.
the picture is 3255


Title: Re: Hammarlund SP-100X
Post by: Scott SWL on April 03, 2021, 10:30:32 PM
This is the one I'm working on
http://amfone.net/Amforum/index.php?topic=46458.0


Title: Re: Hammarlund SP-100X
Post by: WB6NVH on April 06, 2021, 01:26:40 PM
Within the SP-100 line there are some variations.  The SP-110LX is the low frequency model with crystal filter.  The SP-110SX has the "VHF" high end at the expense of the low frequency segment.  I don't recall ever seeing one without it but the "X" is crystal filter, the added plate on the upper left area of the panel.

I found my SP-110LX at the dump's salvage yard. It had a homebrew power supply with it and they made me take a working DX-100 and a box of spare tubes with it.  $ 10 total.  The tubes were not even related, they were new in box Genalex KT-88's.  What a shame... :)

I got my SP-110SX on eBay for about $ 50 back in the 1990's before feeding frenzies and sky-high shipping ruined that venue.  Shipping from Los Angeles was reasonable (300 miles away.)   It has the names of 1940's previous owners penciled in underneath the bottom cover.

These are neat receivers!


Title: Re: Hammarlund SP-100X
Post by: Scott SWL on April 14, 2021, 06:38:52 PM
Replacing the crystal filter shaft is not terribly hard, you can press the pin out of the collar with a carefully placed vice-grip, and small pin


Title: Re: Hammarlund SP-100X
Post by: k6hsg on April 14, 2021, 08:42:12 PM
Thank You Scott
I hadn't looked at it closely and thought that I would need to find a replacement capacitor.


Title: Re: Hammarlund SP-100X
Post by: Scott SWL on April 25, 2021, 06:42:33 AM
I replaced mine on my SP-400 with a 1/4 " plastic rod, and it works fine.


Title: Re: Hammarlund SP-100X
Post by: w1vtp on April 26, 2021, 04:56:43 PM
I have a Hammarlund SP-100X That I bought probably 20 years ago when I lived near Springfield Missouri.  It is serial 2935.  At the time I powered it up and it worked sort of for a short while.  Then one of the screen capacitors shorted and let the smoke out of the resister.  I started replacing the capacitor inards and then let the project slide until today.
I have been following this post with interest and decided that it is time to get it working.  
It appears to be as built except for the first audio transformer.  
  I have two other Super Pro's.  Serial 3255 which has the SP-200 front panel, Sprague 600 line Tubular Condensers and the 100 glass tubes.  The serial is the SP-100 range but looks like a 200.  it has the correct audio transformer so I will probably use it.  It also has an incorrect square meter.
  The other 200 is a late, built during the war, receiver serial 16116.  It looks pretty original and I will probably keep it as is.I currently live in Picture Rocks, Arizona near Tucson.
I would appreciate any and all comments




Never turn this vintage receiver on without replacing the wax paper caps and any electrolytics.  Access is easier if you take the tuner unit out. It's relatively easy but be careful.  Once that unit is out you can get in with the soldering iron and solder sucker and not wreck anything.

I had one and foolishly gave it away.  I had it as a novice operator going to General and then Advanced.  It is on whale of a receiver for am and if you have the one with the xtal filter a good CW receiver.

Treat that masterpiece of design well and you will be rewarded.

Al
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands