I saw the Amazon link , what did you pay for it BTW?

 

The new one I ordered yesterday was $ 12.60 , the one I broke yesterday was $13.90 2 years ago . go figure .
thanks
animal

 

SO question , is that just hot glue they dab in each corner where the board hits the heat-sync ? I want to remove the board from the heat-sync & look at the bottom of the tall cap to the left of the D4 & D6 diodes which feels a tad loose to me . Just want to make sure that I'll be able to put it back together the correct way .
thanks
animal

 

Yes, you can slice it of with a small razor knife etc.

 

Cool ,
thanks
animal

 

Ok , so I removed the board from the heat-sync to check the solder connections in the tall cap & everything looks good . There no signs of over heating anywhere . Is there something I should check out or replace while I have the board out of the
heat-sync ?
thanks
animal12

 

So do you have the external transformer hooked up? If so trace the AC output to the two large diodes to GND,
It is a very simple circuit.
You should have the DC on the large electrolytic cap.

 

Yea external xfmr is hooked up & supplying voltage like mentioned above . I'll give that a look see tomorrow .
thanks
animal

 

Then you should had the DC supply on HD2.

 

That seems to be the issue . Like mentioned above with the AC xfmr installed & putting out the 20VAC there is no DC voltage on HD2 . That is what the problem is with the board . No DC voltage at HD2 , but there is AC voltage going into the board from the xfmr. So It is being stopped somewhere between the 20 VAC in pins & HD2 .
thanks
animal

 

The circuit, IIRC, could not be simpler !
AC to a couple of rectifiers and a large cap, you should be able to trace the printed circuit quite easily.
The one I encountered had a fuse blown, .Is F1 OK?

 

YES the fuse is good!
thanks
animal

 

Spent some time the MC2100 today . I have 16 VDC coming out of D4 & D6 , the 2 large diodes which are right next to the tall cap in the lower left in pic 1 in post one . Still no voltage or pulses on the corresponding pins on HD2 & the fuse is still good . I have no clue what to try next .
thanks
animal

 

Do you have any voltage on the HD2 pins? 1 & 6 are the common and pin 2 is the DC+.
From the rectifiers to the HD2 is just short traces?

 

Nothing on HD2 Pins , no voltage , no pulses if I run a magnet on the reed switch . nothing . I believe it's 1 & 8 are common .
thanks
animal

 

Inspect and trace the source (diodes) to the HD2 itself, copper traces..

 

10-4
thanks
animal