Series V RangeMaster
Owner’s Manual
April 2020
1
Thank you for purchasing a HardWay RangeMaster V. Here are some things you
should know: There will be a test later.
The HardWay RangeMaster is a very accurate reproduction of the original legendary
Dallas Rangemaster Treble Booster of around 1967. A total of 8 Series V units were
built, numbered from RMV001 to RMV008. (RMV001 was the prototype). The serial
number is written on the bottom outside of the unit, and on the inside, on the cover.
Not very many original Dallas Rangemasters were built (nobody knows how many)
and they were hard to find, even in the 1960s, even in England, where they were
made. Moving ahead to the 21st century, I saw one on eBay the other day, listed for
$5,000. Seriously.
The Rangemaster was a very simple circuit, centered around a Germanium transistor
(usually a Mullard OC44 or NTK 275 or a Mullard OC 71). The original circuit consists
of 1 transistor, 3 resistors, 4 capacitors, a potentiometer, a switch, and a battery.
That’s it.
The Welwyn preset pot was 10K Ohms. The boost knob was scratchy when adjusted,
due to the DC voltage present on the pot. This is the way the original was designed;
it is normal for this device.
The Series V HardWay RangeMaster has three PNP Germanium transistor modules,
selectable with a
three-way rotary switch
on the back of the unit. Each transistor
module consists of the transistor, the bias resistors and a 50 µF capacitor. The three
transistors included with the Series V RangeMaster are OC76, OC44, and AC125. The
gain of the transistors used in this series ranged from 82 to 112. (True gain, which is
apparent gain minus leakage.)
Series V also has a
3-way frequency cutoff selector switch
on the back of the unit that
changes the boost frequency from “Stock” to “Wide” or “Full”. The stock (middle)
setting is as the RangeMaster was designed in 1966, a true treble boost. The upper
“Wide” setting expands the boosted range to include more mid-range frequencies,
and the lower “Full” setting boosts the entire range of a normally tuned guitar.
