An ancient piece a test equipment, a G5NI (B'Ham) Ltd monitor scope or oscilloscope, which comprises a small round cathode ray tube in metal case with one toggle switch and four rotary controls on front panel, is being sold by the Radio Society of Great Britain.
The unit (shown right) is one of a number of surplus items which range from coil winders to transceivers, test equipment, accessories and prototypes being sold by the RSGB Museum that are surplus to the requirements of the National Radio Centre at Bletchley Park. The best examples of equipment that showcases amateur radio across the years are being retained for display, and there are a number of other items—such as military radios—that are being loaned to other exhibitions within Bletchley Park. The remaining, surplus items are being offered for open sale via eBay.
Also amongst the test equipment is a Weston model 774 type 4 valve tester in hinged wooden case with attached lid (pictured left). Includes manual and some accessories as shown in photograh. A transformer of some sort appears to have been affixed to the side of the case in a manner that does not appear to offer complete electrical safety, so caution is advised. Includes Test Data for Signal Corps Tubes information sheet taped to inside of lid.
Also in the sale is a Marconi Instruments FM/AM signal generator type TF995A/5 (pictured below). The design frequency coverage is 1.5-220MHz in 5 ranges. Output ranges from 1uV to 100mV. There is also a set of 4 antique radio coil winders, believed to date from the late 1920s or 1930s. Manufacturers include R Sheargold & Co and A W Knight.
A number of the items for sale were custom one off home-made units and include frequency converters, power supplies and a tripler from 144MHz to 432MHz which uses valve technology on metal chassis. Commercial manufacturers equipment featured in the auction include Evershed & Vignoles, Labgear, Webbs, GEC, Heathkit, Toyo, Tektronix, Beckman Industrial, Ferranti, Kenwood, and Lowe.
There is only a couple of days left to bid on some of the items so for more information see www.rsgb.org/auction/.