Heathkit IM-4180 Modulation Monitor I.C. question,

[CaptDon]

I have two IM-4180 units that came to me for repair from another ham operator. Both were devastated by dry cell leakage. I got the lesser damaged unit working and calibrated and it is a very useful piece of gear. I am now starting on the heavily damaged unit. The 8-pin I.C. sockets are bad and will be replaced. The CA3130's in the TO-5 cans have damage to their leads. Heathkit only shows the TO-5 style I.C.'s in the assembly instructions but the DIP version would be so much easier to deal with. Does anyone here have experience using the CA3130 DIP style as replacements? I don't think the metal can is returned to any ground / earth shield lead so it doesn't seem to be a matter of shielding causing Heathkit to prefer the TO-5 style. Any insight here?? I can buy either but would prefer the DIP package. The pinout is the same for both. Thanks!!!

[Wallace Gasiewicz]

Capt   

I have not had your exact problem with this particular unit. 
But I have replaced lots of can op amps with DIPs.   
I think some of those op amps were CA 3130.

I did this for the reason you stated, easier to physically deal with using a socket. Otherwise I use a socket and put the can into another socket so it is easier to put in and take out. It is a lot easier to install the can into a socket when the socket is not on the board. Then you can also easily remove the op amp and change if needed. 
This is probably not optimal for very high freq stuff, but I have had no problems with the double socket.

[CaptDon]

W.G., that is a good idea to put them into an 'auxilliary socket' so to speak. I think I will order up a bunch of the DIP style CA3130 devices and start to swap them in to the working unit one at a time to observe the effect. I could then also take the 'pullouts' and place them into their own carrier socket. The IM-4180 used 10 AA batteries internal to the unit and no leakage protection was provided. I suppose many of these units were simply too damaged to be worth repair? They are a very useful piece of gear when calibrated and working. I guess so many of these sat on a shelf, seldom used and battery leakage onto the PCB was the grim reaper. The upside is the tuner assembly is above where the damage occurs and seems to survive quite well.

[Wallace Gasiewicz]

the round leads stick much better in round machined sockets,rather than the other spring sockets.