I have a Hammarlund model SP-600 I am offering for sale. This receiver is unique and rare in that is was modified by ITT World Communications/Mackay Radio for use in their WSL HF receiving installation in East Hampton, NY. I have been told that ITT/MacKay modified about 25 or so of these receivers for use at WSL, and only a few are known to survive. The ITT/Mackay Radio model number for this receiver is CNY-2018D.
It is one of the later series SP-600s, with all ceramic disc capacitors, and none of the troublesome “bumblebee” style capacitors.
The modifications performed by ITT/Mackay include the following known to me:
1) Converted the single-ended 6V6 audio output stage to a single 6SN7 voltage amplifier driving a high-quality UTC A-25 plate-to-line audio output transformer. As such, this receiver provides a true high-fidelity 600 ohm balanced, line-level audio output. I am of the opinion that because of this modification, this SP-600 offers about the best receive audio quality of any vacuum tube HF general coverage receiver I have ever heard, when driving a high-quality outboard amplifier/speaker combination. I believe the audio quality is better than the R-390 (non-A version).
2) The 25 KHz IF output is brought out through a BNC port located on the rear of the receiver, for driving ITT/Mackay-specific equipment, such an ISB (independent sideband) converter, etc.
3) Provision is made for front panel selection (via a 2-position rotary switch) for internal or external HFO and BFO injection. This was done so a pair of these receivers could be used for dual-diversity reception.
4) Provision is made for IFO (IF Oscillator or Output; I am not sure which) on or off, via a front-panel mounted toggle switch.
5) Provision is made for AGC fast or slow time constant selection, via a front-panel mounted toggle switch.
I have fully tested this receiver, and it works as it should; it is plug-and-play. The cosmetic condition is excellent, with no corrosion, etc., and it is one the nicer appearing SP-600s I have seen over the years.
I acquired it from WSL in 1986, and I have two of them, one of which is installed and in use in my shack. This one has been sitting on the shelf unused here at W2XR for the past 27 years, and it’s now time to pass it on to someone who can make good use of it.
The price is $650.00, plus the cost of shipping to your QTH.
Feel free to send me a PM at
triodes@optonline.netThanks & 73,
Bruce
