Wiltron 640 network analyser - UK Vintage Radio Repair and Restoration Discussion Forum

lesmw0sec · 11th May 2016, 1:53 pm

I was recently given a nice Wiltron (Tektronix) network analyser model 640.
This has a 640G sweep gen and two 640E Log amplifiers.

I have the necessary SWR bridge but do not have the 640T external RF detector. This is clearly a simple diode based device which I could probably make, but I am a bit confused as to what it comprises. The diode and the RF input both have one side directly to ground, yet the plug-in makes connections to a differential input. There is also a thermistor in the detector, which I presume is for temperature compensation.

Whilst I am unlikely to use this for other than as a glorified wobbulator, it would be nice to get it fully to spec. Does anyone have experience with this beast and could tell me the internal configuration of the external RF detector?

Les.

11th May 2016, 1:53 pm	#1
lesmw0sec Octode Join Date: Jul 2009 Location: Carmel, Llannerchymedd, Anglesey, UK. Posts: 1,509	Wiltron 640 network analyser I was recently given a nice Wiltron (Tektronix) network analyser model 640. This has a 640G sweep gen and two 640E Log amplifiers. I have the necessary SWR bridge but do not have the 640T external RF detector. This is clearly a simple diode based device which I could probably make, but I am a bit confused as to what it comprises. The diode and the RF input both have one side directly to ground, yet the plug-in makes connections to a differential input. There is also a thermistor in the detector, which I presume is for temperature compensation. Whilst I am unlikely to use this for other than as a glorified wobbulator, it would be nice to get it fully to spec. Does anyone have experience with this beast and could tell me the internal configuration of the external RF detector? Les.