Dynatron Merlin or Ether Conqueror Schematic

[saddlestone-man]

Hello All

I'm looking for a schematic of the audio amplifier sections of Dynatron models Merlin or Ether Conqueror. I can't find these on the service data DVD-ROM or the Radiomuseum. I find the model naming and numbering confusing, so it may be there, but no luck for me so far.

I'm particularly interested in the push-pull triode driver to push-pull triode output stages which I believe were used in these models.

Many thanks for any help you can give me.

best regards ... Stef

[Synchrodyne]

The short answer is that a schematic for the Dynatron LF59 amplifier might provide what you are looking for. This was the amplifier part of the initial post-WWII Ether Conqueror chassis. I have the schematic for the LF59B. As I downloaded it from somewhere unrecorded, I won’t post it here but please send me a PM and I’ll send you a copy.

The LF59B had a pair of PP3/250 triodes in push-pull, preceded by two HL41 stages, apparently the first an amplifier and the second as a phase splitter. At least it does not look like a push-pull phase-splitter.

The longer answer is that as best I can determine, the “Ether Conqueror” was the name given to Dynatron’s top chassis system in the immediate post-WWII period. It was used in several radiogram models – each of which had its own model name and number - and in the Merlin console radio receiver. The initial version used the T69 tuner/control unit (usually referred to as a tuner) and the LF59 amplifier. There seem to have been four iterations of this, defined by the T69A, T69B, T69C and T69D tuners. That said, I am not sure whether the T69 (unsuffixed) and T69A were separate models, or whether T69A was the first and T69 simply a generic designation I don’t know. The amplifier appears to have gone through LF59, LF59A and LF59B iterations. The T69/LF59 series used Mazda 4-volt valves.

The “Ether Conqueror V” was announced circa 1951 October as a “1952” model. I assume that the “V" suffix was the Roman numeral 5, meaning the fifth iteration in the Ether Conqueror series, but that is unconfirmed. This ensemble comprised the T99 tuner and LF612 amplifier. These used Osram miniature valves, and the LF612 output was a push-pull triode-strapped KT66 pair. The “1953” Ether Conqueror V was announced circa 1952 September, and was said to use the T99A tuner and LF612A amplifier. There was a T99B iteration, but I am not sure where that fitted into the chronology. Possibly it was the “1954” model.

An even higher performance chassis combination, the “Ether Marshal” was announced in 1954 September. This included the T139 bandspread tuner and LF613 amplifier, the latter I think not a lot different to the LF612. This was used in some of the radiogram models, and the Merlin was also changed over to this chassis for what I think became its final iteration.

The Ether Conqueror chassis stayed in the range alongside the Ether Marshal for about a year, but does not seem to have been in the “1956” range. New for that model year was the “Ether Pathfinder” ensemble, comprising the T10 FM-AM tuner (a true tuner, without an AF control section), TC10 control unit and LF10 amplifier. The T10 was quite highly specified on the AM side, but I think not quite at the T99 level. My best deductive guess is that the LF10 used the Osram 912 circuit; it had an ultralinear N709 pair. (The later LF20 was basically a Mullard 5-20). Dynatron’s move from triode to ultralinear outputs was in line with the industry trend, and the move to using valve-maker rather than its own circuits was at the time becoming quite common for some of the smaller amplifier makers. The Ether Marshal chassis remained available until around 1959, being listed in Hi Fi Year book 1959.

Re the Merlin console receiver, some of the applicable model numbers were: B129 (T69/LF59), B1512E (T99/LF612) and R1712 (maybe with a suffix letter; T139/LF613).


Cheers,