Heathkit IM-48(IM12,HD-1) IM-58 (AA-1 IM-22 ) troubles

[s-petersen]

Hi Guys and Gals,
I have a Heathkit AA-1 audio analyzer and a IM-58 harmonic distortion meter.
They both have issues.They didn't work when I bought them.
I am working on the IM-58 currently. So far I have found several bad solder joints,and a few incorrect resistors.
I have been able to calibrate it successfully, but there is still a problem, the sensitivity control on the voltmeter
works on the higher settings, but the 1v and 3v are way off. The manual I have is missing many pages(I have not found a complete manual online),If anyone has a manual, Does it have a pictorial of the back of the completed control?, or can someone take a picture of their working unit?
Thanks,
Scott

 

[nerdorama]

I have a manual which seems complete. Is this the picture you need? You can PM to me with your email if you'd like a copy of the manual as I have it.
John

 

[s-petersen]

If you look where it says sensitivity,the control has no detail,the unit has 4 resistors and jumpers across the back that are not shown,I "think" the user was supposed to assemble it,then use this pic to install it,it was either that,or it came pre-assembled,I am not sure.
I have the same pic already.
Thanks!
Happy holidays!

 

[s-petersen]

I just found a German assembly manual with the info. Thanks!

 

[nerdorama]

Can you share the link for the German site? I'd like to snag a copy too.
Thanks,
John

 

[s-petersen]

Here it is:
http://www.rainers-elektronikpage.de/SM-HEATHKIT/HEATHKIT-Klirrfaktormessgerat_IM_-_12_E.pdf

 

[s-petersen]

I'm a little frustrated with these things,I have to take break with the IM-58, It was built wrong (683k swapped with 68.3k) and partially worked,I fixed it, now it's worse,grrr!

I jumped to the AA1,I got further with it. The range switch had a precision resistor drift 30%.I moved to the IM calibration and the oscillator is running at 3k instead of 6K. I tried the calibration procedure anyway and cannot adjust the level to 100%, it's either 0 or pegged,there is no in-between.