Hello all,
Been a long time since I have been on this site. I recently acquired a virgin early 1200. ( 5000 range SN, 1.4 ver firmware ).
It has recently developed a problem. When you turn it on the display will come up "step 00 hz" and will be locked in that position. If I turn the scope off it seems to work normally ( but with no scope ). I checked ( and replaced ) the backup battery as well as checking the caps on that board. All of the P/S voltages are there but all seem just a tad low.
Any thoughts that might steer me in the right direction?
Thanks in advance,
Darrell
IFR 1200 help needed
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Re: IFR 1200 help needed
re-cap the power supply.
I would replace the two large caps on the AC supply and all of the caps in the DC - DC converter
You can try to run off of DC and see if it does better but I would still re-cap regardless.
I would not replace the Tantalum ones ...they do fail but when they go it's usually a short and not an open.
The caps on theses older units need to be replaced proactively since when they fail they leak and oftern damage the PCB's
I would replace the two large caps on the AC supply and all of the caps in the DC - DC converter
You can try to run off of DC and see if it does better but I would still re-cap regardless.
I would not replace the Tantalum ones ...they do fail but when they go it's usually a short and not an open.
The caps on theses older units need to be replaced proactively since when they fail they leak and oftern damage the PCB's
Re: IFR 1200 help needed
Jry,
Thanks! As it turns out you were right on the money. 2 bad caps inside the DC/DC converter took care of the problem. I went ahead and replaced the others as well.
Darrell
Thanks! As it turns out you were right on the money. 2 bad caps inside the DC/DC converter took care of the problem. I went ahead and replaced the others as well.
Darrell