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63 Volt Battery replacing an Original Eveready 467, RCA VS016, Burgess XX45, Ray-O-Vac 4367, Philco P67, Batrymax B101 (and other) 67.5 Volt Battery, for Tube Radios of the 1940's and 50's, using seven Standard 9 Volt Batteries (including Rechargeables) clicked into Place on Printed Circuit Boards
In a Nutshell
Next summer is coming - sooner or later, and it's time to take your vintage radio to the beach. The battery presented here satisfies the brisk demand from both, sellers and buyers of battery operated portable radios of the 1940's and 50's. Sellers do not longer have to state: "sold as is" or "have no way of testing the radio", and can even include with the radio a (rechargeable) battery. Buyers who bought from a lazy seller, can easily upgrade their accession to a (hopefully) working radio. It is intended to commercialize this product as a kit, containing two preassembled and wire-connected Printed Circuits plus three shell templates to be chosen from four samples. Cheap shipping can be done in a padded envelope
Introduction:
Portables of the late 40's and early 50's ("Beach-Radios" of the pre-transistor age) faced the problem of supplying their tubes with sufficiently high plate voltages while trying to be as small and compact as possible. The bottleneck was obviously the size and weight of the "B"-battery. The standard tube line-up of these radios is: 1R5, 1T4, 3S4, and 1U5, the heater strings of which were powered in parallel with 1.5 Volt from one or more "D" cell batteries and their plates with a 67.5 Volt battery, produced by many companies (Eveready 467, RCA VS016, Burgess XX45, Ray-O-Vac 4367, Philco P67, Batrymax B101, and others) with the same size. Although these 67.5 Volt batteries may still be available, they certainly are difficult to find and expensive to buy and to replace.
The size of a classical 67.5 Volt battery is 91mm x 71mm x 34mm, the size of a conventional 9 Volt battery is 45mm x 26mm x 16.5mm. Accounting for the necessary interconnections, the outgoing electrodes and the shell thickness it is possible to house seven 9 Volt batteries inside an original battery shell, as shown in pict.3. In the following I show how to build an inexpensive 63 Volt battery with the same size as an original 67.5 Volt battery using seven conventional 9 Volt batteries. The new battery can be easily assembled and disassembled without the need of any soldering and can use a wide variety of 9 Volt batteries including rechargeable ones.
Alkaline batteries have around 1.65 Volt/cell, so seven 9 Volt batteries in series will initially have at least 67 Volt (see pict.17). Since the tubes work well with plate voltages as low as 40 Volt, even NiCd batteries can be used (sum up voltage around 50 Volt with very small discharge drop). The batteries are connected via standard 9 Volt snap-on clips (by Keystone), which are soldered onto two printed circuit boards (pict.3). Pict.4 shows the battery before final assembly; a small wooden piece is used to fill the excess volume and to stabilize the battery. The outgoing electrodes consist of "senior" snap-on clips, matching the standardized battery strap of the vintage radio.
According to the specifications of radios using the above set of tubes, the B-battery is discharged with about 7.5 mA, and therefore seven Alkaline 9 Volt batteries have to be replaced after about 60 hours uninterrupted listening, Li batteries would last about 160 hours, and rechargeables about 30 hours.
The 1.5 Volt D cell for the heater string is discharged with 250 mA and lasts about 48 hours. Pict.s 9-16 show to-scale templates of the shells of an Eveready 467, RCA VS016, Burgess XX45 67.5 Volt battery and a generic 63 Volt battery, which can be printed out, cut and glued to house the seven 9 Volt batteries. Higher (up to infinity) resolution templates are available on request, since the mother template is a vector drawing. Pict.s 19 and 20 show the battery resuscitating the venerable RCA 54B5 portable beach radio "Solitaire", a radio made from 24K gold plated metal and catalin, and famous for the photo showing Cary Grant taking his to the beach.
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