Someone on the Antique Radio Forum was asking about the HP 650A test oscillator. They are beautiful vacuum tube R-C test oscillators. The 650A was originally supplied with a Model 65A-16D Output Divider Cable, but they are invariably missing when you acquire a 650A.
The manual provides a complete description of the 65A-16D cable, so I constructed one for my 650A.
I used two small Hammond die-cast aluminum boxes. Rather than hard-wire the cable, I added BNC connectors at each end, so I can use whatever length of BNC patch cord is convenient for the current bench setup.
The top side features a dual five-way binding post for the 300Ω output.
I used fiber insulated shoulder washers to isolate the banana plugs from the case.
Here's the inside of the source side, with the 594 ohm series resistor.
And here's the 6Ω termination end.
I also made up a 12:1 divider to provide about a 50 ohm output impedance.
The 50 ohm output is the BNC connector.
The divider consists of a 549Ω resistor and a 49.9Ω. This gives about a 48Ω output impedance, factoring in the 600 ohm output impedance of the oscillator. I should have used a 52.3Ω instead.