Return Loss Bridge

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[rtrn-3]

It is in a old Texscan RCB-3 case.  Someone originally transmitted full power through the bridge and destroyed just about every component.

[rtrn-1]

Internal component picture.  The little brass springy thing is a variable capacitor.

[rtrn-4]

You get the idea... be sure to keep the leads short.

[gbppr-rtrn-1]

Green Bay Professional Packet Radio version in an old MMDS case.

[gbppr-rtrn-2]

Insides.  The yellow wires are gimmick capacitors used to tune the bridge.  This version has a 51 Ohm resistor soldered in for the reference termination.

[gbppr-rtrn-3]

Side view.  Note I used 5% tolerance, 51 Ohm resistors, they should really be 1% tolerance 49.9 Ohm resistors.  Close enough.

[gbppr-rtrn-4]

DC out on the left, RF input in the middle, Z2 on the right.