Graymark

Graymark Micro-Museum

The Graymark Micro-Museum includes 5 constructed kits that are fully restored and functional; a number of original kits that have not be constructed; and a number of manuals and documents.

A 501 Crystal Radio was one of the simpler kits.

The 506 radio has 5 tubes (follows the American 5 tube radio lineup – 50C5 35W4 12AV6 12BE6 & 12BA6).  It covers the standard AM broadcast band and a Shortwave band.  It also has a phono jack input to function as an audio amplifier

The 510 AM radio also uses the 5 tube American radio lineup

The 511 regenerative All Band Radio used 3 tubes and plug-in coils.  By placing the receiver slightly into regeneration, it was possible to receive CW and SSB signals.  However, stability & selectivity were very poor.  Detailed info is here:

http://www.ka2c.com/graymark-511/

The 515 micro-power AM transmitter used 3 tubes.

An unopened 505 AM transmitter kit

Manuals for some of the kits.