CGC advertised in QST for a second radio in order to try and
repair the first. A Colonel, in the USAF, from NH showed up in the front yard
of our house on Merriam St. in Lexington MA, hawking the HA-88960
chassis. This was soon after the move to
Merriam Street, which puts the purchase in the 1972 to 1974 time frame.
Dad had advertised for another SX-42, presumably as a donor for
The original SX-42 (HA-89503) may not have been working, it may have been on the shelves in the basement at Merriam street early on in 1972 - 1974, waiting for service. At the time I had yet to be bitten by the radio bug, although I was interested in the discipline.
Given the clear association of the manual and HA-89503 there seems little doubt that this relatively unmodified chassis is the original CGC purchase. Furthermore HA-88960 clearly does not match the manual. The 6SL7 "Audio Inverter" dual triode of the manual, and HA-89503, is not present in HA-88960. In its place there is some other component. It is not believed that this area of either radio had been modified by anyone.
There is an additional RCA jack that was mounted in the center of the nameplate on the back panel of HA-89503 but it appears to have not been wired to anything or is no longer wired to anything. This is no doubt the infamous "phono preamp port" that CGC decided would be a good thing for his audiophile interests. Young people do silly things. CGC claims this modification was done "shortly after purchasing the radio", which probably means he was not more than 20 years old when he thought it would be a good idea. I wish he had chosen a better location or not bothered to do it at all.
CGC claims serial number HA-89503 had a couple modifications. One was the addition of a phono cartridge preamp. This modification was done soon after purchase by CGC. At the time the Pickering company had just released a new magnetic reluctance phonograph pickup with far better fidelity. The problem was that it also required far more gain than other pickups. The internal preamp of HA-89503 was the first attempt at making use of the new Pickering cartridge. This did not have enough gain so an aftermarket preamp was purchased or copied, and stuffed into the chassis.
A short time later the same preamp became available as a stand alone unit with its own power supply. With this new arrangement, it was possible to remove the modifications to HA-89503, and return it to its normal configuration, except for the hole drilled into the chassis for the RCA jack. The radio then remained in this configuration for some time.The next shot is of the main deck HA-89503. There is quite a bit of dust, and oxidation. This is going to take some work. However, it isn't as bad as some of the pictures of "boat anchor" chassis you can find on the web.
CGC is unswerving in his assertion that an attempt to make the HA-89503 radio demodulate SSB was made by the son of one of the bosses at C&K components. "Kincade's son" supposedly did the work. The radio was loaned to Kincade and his son, since none of CGC's children at the time seemed interested in radio or electronics. Given the time frame (late 50's to early 70's), CGC's children were far too young.
This chassis has been butchered. After more discussions with
CGC this ratio may have arrived in this condition. The Colonel in
the USAF, who was the previous owner, was the head of an electronic
maintenance group. It would seem plausible that this radio as
well had been modified for SSB. After WWII the amateur radio
community started to pick up on SSB techniques. Apparently SAC made SSB its standard
form of radio communications in 1957. Keeping these things in
mind, it stands to reason that HA-88960 would also have been subjected
to the SSB treatment. However, in this case the person or persons
responsible were not delicate about it.
Transformers have been removed or added, tubes, and capacitors added, and large holes cut in the main deck... butchered.
The modifications are placed in the circuit at or about the "AM. DET. & NOISE LIMITER" tube, a 6H6 type. This is where you would think an SSB modification would be made.
Note also that an additional audio preamp would not be placed in this part of the circuit. It would appear between the phono input jack (J1) and C106, the audio amplifier DC blocking capacitor. Indeed, on this chassis, the RCA plug phono input jack has been removed. Again, it seems unlikely that this chassis had been modified for high gain phono type applications.