The 828 was the TOTL receiver for the x2x series (1972-74 model years). Service manual
here
60W RMS both channels driven into 8ohms @ 1kHz. Probably the closest pre FTC measurement other than the 20-20000Hz which is 54W.
The "missing" lamp is most likely there, but dead. It's a 8V 250 or 300ma fuse lamp. The latest thing is to change them out for LED units. Personally I don't like LED's in the PIONEERS. But that's something you'll need to figure out for you.
Speaker plugs can be made cheaply from AC Wall plugs. Quite a few threads on them here in the forum. Seems like a new guy starts a new thread on this every year, and the same pictures, parts, and procedures are re-iterated. SEARCH AK via Google for this.
There are some "TROUBLE CHILD" transistors in the 828. These should be pre-emptively replaced to prevent future problems. They get noisy, breakdown, and will cause what i call "Rice Krispies" (snap, crackles, and pops) when they start going. The Main culprits are 2sa725, 2sa726, and in the case of the 828, 2sc1312's. Replace the 2sa725/726 with KSA992's, and the 2sc1312 with ksc1845's.
As for caps. The small value "SKY BLUE" SANYO caps are solid aluminum electrolytics. These MUST GO! They are responsible for a lot of the problems associated with these units(not a IF situation but a WHEN they go, same for the transistors above). Depending on the value and room available, a film cap of the same value is recommended vs an electrolytic. Above 2.2uf and the physical size of the film caps grows drastically.
Last item. The plug on the side of the unit is for an EXTREMELY RARE, Transformer for a Low Output Moving Coil phono cartridge. Hen's teeth are plentiful compared to this transformer. If you use a MM cart don't worry about it. If you use a MC cart, an outboard transformer/step up trans. connected into AUX will work fine.
