Found data. From September 1946 QST, page 117, full page ad for the
Cardwell Fifty-Four.

1. Full turret R.F. Section
2. Wide coverage with coil strips to 40 mc - extra strip goes to 54 mc.
3. 100 and 1000 kc calibrator.
4. 5 degrees of selcetivity.
5. New noise limiter.
6. Band spread dial calibrated directly.
7. 10.5 inch direct reading dial.
8. Temperature compensated oscillator.
9. (This is an interesting one). Mechanical control shafts are brought out
back of set for linkage to other units, such as excited or transmitter. Can
you imagine the tracking nightmare for the homecuilder?
10. All aluminum construction (still weighs 78 lbs).
11. Push-pull class A-B output (8 watts).
12. 18 tubes - all miniature.
13. Panoramic adapter jack.
14. Threshold squelch.

They claimed they had a technical bulletin.

In the October 1946 issue, there is a full page ad with a drawing of the
receiver. The technical article was signed by Mack C. Jones. Said a
technical bulletin was available.

Cardwell ad for November and December 1946 was for other products.

Will research 1947 next.

Colin K7FM