SP-600-JX-17, #17045

(Click for full-size picture)	This is an SP-600-JX17, serial number 17045. It was made for the Air Material Command. This is the "diversity" receiver. I did refinish the front panel. I used a darker grey so the engraving and the dials stand out better. I did repaint the black knobs on this one (not the red ones). They were quite dull. I did not try to repaint the meter. I was worried that some paint would get into the mechanism. The frequency and vernier dials were quite clear on this unit, so I did not replace them with dial overlays. I did clean them up a bit. Note that in the process of restoration, I completely disassemble the receiver - I take all the gears off on the front panel and remove all the major assemblies (that come off, that is). I will warn you that the unit, in person, doesn't look as good as these pictures look. I don't quite know why, but the pictures look great, whereas the actual unit has some nicks and scrapes and rust spots on the chassis. I replaced a lot (not all) of the hardware with stanless - especially on the front panel. Every time I took a screw out, I replaced it with stainless, and every time there was a markedly rusty nut or screw that I could get to, I replaced it.
(Click for full-size picture)	I did wash and scrub the sheet metal with a scrubby sponge. No steel wool was used in the process. De-Oxit was applied to all the tube sockets. The chassis did not need any work - it was relatively clean and square. It was apparent that this receiver had not been dropped or otherwise mishandled. There were no bent edges or crushed corners. I replaced the missing tube hold-down clips on V3, and V17.
(Click for full-size picture)	This is where I spent most of my time: the RF deck. All the caps were replaced with 600V ceramic. A number of resistors were replaced as well. I used a lot of shrink-tubing on the leads to prevent shorts but still allow you to get a tool in to align it. A number of wires were replaced. Several out-of-spec resistors were replaced. The caps were dressed to hug the ground plane wherever possible. I replaced the first RF tube with a 6BZ6 for added sensitivity. You notice that the FCU (the crystal oscillator) has the 6AH6 tube on this model (as opposed to the 6AC7 on other models).
(Click for full-size picture)	This shows the recapping job on the IF and AF sections. All the orange items are 600V SBE (née Sprague) "Orange-Drop" 716P capacitors. A number of resistors had to be replaced in this area as well. Several capacitors were bad and were replaced. Most of the high-resistance (500K and greater) resistors were wildly out-of-spec and were replaced.
(Click for full-size picture)	This is the rebuilt power section. I replaced the electrolytic with 47-uf, 450-V special high-ripple tolerant, long-life, electrolytics. You should be able to pass this one down to your grand-children.
(Click for full-size picture)	All the miniature tubes have the IERC heat-sheding shields or their Cinch equivalents. These are the only tube shields known to actually increase tube life.