Re: IF core positions
Thanks guys.
This is for an Ekco A22 and the cores are on separate bobbins in the can, probably about an inch apart. But there must be coupling between those sharing the IF can.
I was trying to be clever and with the use of a wobbulator get a nice (shallow) double hump for greater bandwidth. On strong signals (i.e. my pantry tx) the set was motor-boating with the volume turned up. I fixed it with an extra 47uF across the second PSU electrolytic, but that shouldn't be necessary at all! (The PSU caps are new from the BVWS.)
After days of going round in circles I think the problem was somehow caused by my IF tuning. By following the sheet instructions properly (just peak for max at 465 kHz and don't try to be clever!) I think I've cleared the motor-boating anyway.
Ian
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