Amber 3501A Distortion Analyzer?

[arts]

Yes,certainly good news dodging the ER,but I'm missing a fair amount of skin.Apparently,men of my age should not be doing stupid things like this

I'm in Chateauguay,just on the outskirts of Montreal.My shop is for my own use,and is not open to the public.
I've always preferred the SMPTE IMD method for power amps,,especially for tube equipment,as it really challenges the entire unit under test,from the power supply on up.
I've found the CCIF IMD method is more suitable for preamps and other low-level devices,particularly solid state equipment.

When I got the 3 units home, the first thing I did was remove the bottom covers,hoping for the IMD mod.Darn,not there.
I'd really appreciate it if you could dig out that board,thanks!

 

[rcs16]

Road rash is a bitch, I know, I road a Yamaha XS-1100 for 20+ years Went down twice, rain/streetcar tracks,oil slick. Be careful.
I guess you know now, that the model number is the key to the options inside, like I made sure I bid on a 3501-03110 as a spares unit to match the mint 3501-03115.
here is a pic of 3401-460-02 with a bunch of barnacles on it, from model 3501-03110 s/n 3501-83041118. Not sure what rev/sch the mods make it. The mint one, s/n 3501-84501405 uses a 3501-460-04 pcb.

 

[arts]

It's kind of silly really.I've been riding (and collecting) old Norton,Triumph and Matchless motorcycles,in all weather conditions, since 1978.Fabulous handling,very light bikes with virtually no braking whatsoever compared to modern machines,and I've yet to drop one on a public road.Scrambles,trials and other off-road silliness doesn't count
I still can't believe I wiped on a bicycle.....

That's a beautiful board,but being double-sided,it looks a little too complicated to duplicate.For such a popular series of machines,there doesn't seem to be a lot of information or parts available.

 

[rcs16]

Actually many of the parts are still in production. Lots of TL072CP and NE5534AP around but some others, long obsolete are scarce, the OTA,CA3280?, photocoupler clmxxxx?, the muti-ganged frequency pot.
You have lots of spare parts now that you have 3 units.
That IMD pcb is not very difficult to reproduce. It is a cheap one, all you need is layout and pcbway fab . It is a fair bit of work, test etc,.All the parts are still available and common or subs are available. I guess it depends on how bad you need it. Maybe easier to find one in another unit and roll it with what you have already.

 

[arts]

I checked the serial #'s tonight: 3501-84291369,371 & 372.
Verified the third unit,and the distortion is somewhat higher than the other two,at about 0.002 to 0.0025 between 50hz to 20khz.This one is the oldest serial # of the 3.
This unit also has a slightly different control panel (extended level markings) and meter scale (no red zone).I took some pics of the control panels,and of the ''special'' filter.
Agreed,reproducing the pcb is not difficult.Getting the artwork is the problem. Sorry about the lousy photography,it's not something I learned much about.