Did Hallicrafters use a doghouse in the SX-101A that the crystal mounted in sockets and exposed
on the top deck next to the osc. tube?
I picked up a spare doghouse and this one is very different than the others I've seen in other
SX-101A models.

Pete

Check carefully. The SX100 and the SX101 used a 50.50 I F and the 101A/111 went to the 50.75 I F. My 111 has the xtals soldered underneath while my 101A has them on top in holders.

Pete,

I have two SX-101A receivers and one of them has the 2nd conversion oscillator crystals on top in sockets. My SX-115 also has the top mounted crystals but all of my others in this family (SX-96, SX-100, SX-101MkIII, SX-111, SX-117) have the crystals mounted internally as does my similar SX-88.

Except for the SX-115 (different 2nd IF frequencies easily identified by the frequencies of the top mounted crystals) and SX-88 (different first IF frequency depending upon range, no selectable sideband via crystal control) the 2nd conversion oscillator is electrically interchangeable within the family. The SX-122 uses the same scheme but doesn't have the 2nd conversion oscillator/mixer built into a separate module but you can take parts from a SX-122 parts unit.

Halli changed the final IF alignment target frequency over time which resulted in a slightly different placement of the bandwidth skirt with respect to the signal but the nominal 50KC IF transformers themselves can easily be aligned to either target IF frequency and the conversion oscillator crystals remain the same. As I noted in a different post, if one (or both) of the 2nd conversion oscillator crystals drift slightly it is possible to align the final IF and BFO to a new target frequency in order to ensure that the selectable sideband system still works as designed.

Rodger WQ9Eb

Mine are on top and Ive also had them in the bottom which I suppose might be a later cost reduction. With a little work I can get this beast moved and find the serial # if you want.

Carl

Hi Carl!

Thank you for offering, but no, don't bother!

I was just curious if this doghouse was ever used in an SX-101A
model. The crystal frequencies are the same. I damaged mine when my sweatshirt
caught on the top screw for adjusting the osc. and damaged the form.
This doghouse is a replacement. Since the RX is working fine I may leave alone until the
next I need to work on it and then swap assemblies.

Pete