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Looking for manual 2-posn coax switch - THREE pole

Looking for manual 2-posn coax switch - THREE pole

Looking for manual 2-posn coax switch - THREE pole

For a project at work, I have a requirement for a manual (operated with a knob) 2-position coaxial RF switch with at least THREE poles. The tricky bit is the 3 poles.

I'm trying to avoid using a coaxial relay (or relays) because then I'd need to provide a power supply. The RF connectors can be anything common (such as BNC, TNC, anything...). Power is up to 50 watts. Frequency up to 500 MHz. Requires reasonable isolation (maybe 60dB minimum) across the open ports.

Does anyone know of a supplier for a knob-operated two position coaxial switch with at least THREE poles?


RE: Looking for manual 2-posn coax switch - THREE pole

The usual suspects seem to only offer SPDT in manual.  However, RLC does offer multiposition switches with manual control.



RE: Looking for manual 2-posn coax switch - THREE pole

It appears that they have nothing with 3 poles. Their multiposition switches have only one pole.

RE: Looking for manual 2-posn coax switch - THREE pole

I've just received some info that confirms that I can use a simpler switching scheme. So the requirement for 3-pole switching has (thankfully) gone away.  Thanks.

RE: Looking for manual 2-posn coax switch - THREE pole

I avoid RLC 24/7/365.25/untildeath.

My least favorite company. My bad experience with them is they shipped me $25K worth of 1x2 and 1x6 RF coaxial switches, and the switches were very flawed, they wouldn't replace them or give any money back, even for parts that didn't work.

I measured and time lapsed X-ray photographed their switches as they self heated. Their center contacts on their coaxes moved apart because they were assembled with screws that loosen during heating (they needed alignment dowels but their design didn't use that). The contact point was edge to edge after they heated and hence became inductive and looked like a low pass filter with 25 dB loss at 18 Ghz. This happened on 35% of them. Their sensors that provided feedback on whether they switched or not didn't work on half of them upon initial receipt, even without self heating. Hence they knew they made and shipped bad parts. It's all about the money.

RLC's response; "we tested them, they looked good, your technician made errant measurements, no money for you".

This was 12 years ago while I was at Raytheon Goleta.
I should forgive and forget, but like murder, there's no statute of limitations for Engineers receiving bad parts from bad management, especially when they don't fix their problem.  Two years after the incident, I was in contact with a VP from RLC, he said he'd look into it, never heard from him again.

I reordered the whole set of switches from Sage Labs, got better results although theirs had problems too in about 10% of them, at least they replaced any bad ones without effort. RLC = Grrrrrrrr!


RE: Looking for manual 2-posn coax switch - THREE pole


Think about 3 rotary ( manual ) coax switches cobbed together and modified with one shaft extending down through the wafers of your new 3 layer package..


73s de Dave AA1A

RE: Looking for manual 2-posn coax switch - THREE pole

Hi Dave. I might try something like that for a personal project, but at work it would not be feasible due to the cost of labour (Engineering, Drafting) and requirements for strict design control (test plans, etc.). Luckily I was able to find a (clever smile ) design shortcut that eliminated the requirement for three poles. But thanks for the suggestion.

PS: Nice callsign. It must be at the very top of some lists.

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