Echoes from a distant past
Part two - The Two Transformers
Part one - Siemens Rel. send. 22bPart two - The Two Transformers
Part three - The Rohde & Schwarz NGU laboratory power supply unit for vacuum tubesPart four - The Rohde & Schwarz Vacuum Tube Meter URI BN 1050Part five - The Rohde & Schwarz UVN BN 12001 NF MillivoltmeterPart six - The Nordmende digital multimeter DIVO 3355 (with Nixie tubes!)Hello,
as announced in the first part, today I'd like to show you the two transformers, one is an adjustable isolating transformer of an unknown brand (the RRTGL) and an adjustable power supply from
PHYWE.
Front view: left the RRTGL, right the PHYWE 07475
As you can see, they are looking very nice and clean, nearly mint condition.
Let's start with the RRTGL
I haven't found any information online about the RRTGL, the only piece of information was this plate next to the type shield.
But we do have a date code: the device has been tested on January, 19th 1967. I hope, the test was successful.
What I do really like are the instruments. Aren't they gorgeous?
It seems, that somebody replaced the pair of binding posts on the right. I think, the new ones are
Hirschmann PKNI 10The mains socket is a clear hint for the isolating transformer inside, because it has no PEN connector. I'm not sure, but looking at those scratches I have the impression, that this socket has been added as a modification. Maybe the same is also true for the new binding posts. Mains switch, flip it upward for "ON".
Let's have a look in it's back. Backside of the mains socket and the old binding posts with some patina. The current collector.
All three outputs are in parallel, I've measured at 0%, 50% and 100%.
Now the PHYWE 07475. It is an unregulated PSU with two AC and one DC outputs. One AC output is fixed at 6V~/5A which is good for vacuum tube tinkering.
On top there is a nice and useful handle. Clean up aid for the mains cable. Type plate.
Here are some details of what's inside.
Bosch capacitor with a date code of 02/68.
Full bridge rectifier. Transformer with a detailed view to the non-isolated parts of the windings and a detailed view of the current collector.
Some measurements of the outputs. Please note: the mains switch flips upwards for "ON".
The 6V~ output. The 0V~ ... 25V~ output at 0V, 15V and maximum.
The 0V ... 20V DC output at 0V, 10V, 20V, maximum. Output is reading a bit high.
This is the manual which I got with the 07475.
Front cover, inside left, inside right, back.
I hope, you've enjoyed part two. Please stay tuned for part three - the Rohde & Schwarz lab power supply for vacuum tubes, type NGU.
Thank you for watching.