[Boatanchors] General Coverage for Ham Receivers

[Keith Densmore]

Greetings to All,
Over the years I have owned  receivers with a crystal controlled front end.
Usually they are limited to a set number of bands determined by the number
of crystals they contain. The design uses both solid state and tube sets
and includes Collins, Drake, Heath and others.
The only set that had a 'converter' to give general coverage was the Drake
R-4C which used the FS-4 to generate crystal frequencies to give Short wave
coverage from a ham receiver.
I recently picked up a Allied SX-190 and am curious if anyone has played
around with using a DDS generator to expand frequency range of  receivers
of this type. Not much on the internet and there is an array of signal
generators (mostly Chinese). I hope someone can cut through the confusion.
Thanks,
Keith ve3gem