Ham Radio Coax Switch Tear Down

[@n0hr]

"let's find out how on earth it's grounding" Nice line.

[@Philg0jba]

Hi Cal, I hope the isolation between each port of the switch is good enough. 100Watts and 30 db isolation will shove 100mw into the receiver front end of other radios connected. Always worth checking Specs. Phil

[@kg2c]

The MFJ-1702C I use has 60db isolation advertised by MFJ and have checked it myself to be true. I am guessing the ones Callum showed are similar in spec, even the old ones.

[@DXCommanderHQ]

I don't care.. I only use one radio at a time anyway.

[@stargazer7644]

@@DXCommanderHQ Whether the radio is on or not doesn't make a difference. If there's not enough port to port isolation on those switches you'll find the front ends blown in the rigs - even if they're turned off.

[@la7dfa]

@@stargazer7644 It depends what radio it is. In my FTDX101 all antenna connectors are grounded when the radio is off.

[@G5STU]

My Thunderpole CX-201 switch (purchased from Amazon a year ago) is clearly a cheap clone, the internals are not to spec with yours, by a long way. Good to see what a proper switch looks like inside. Cheers Cal.

[@mikemurphy9753]

Never did have any luck with these type switches. SWR's were through the roof. Ended up buying a Alpha Delta switch and solved the problem.

[@baslev]

There are very cheap CX-201 switches on the market most times from China. They look the same outside but used materials inside are not the quality you expect. I discovered that already 30 years ago when I was heavily into CB. Personally I prefer the Daiwa brand for these switches. Good luck perfectioning you shack. 73, Bas

[@tomnapier3910]

I did a similar teardown of my switches about 10 years ago. After what i found I sold all my similar type switches except 1. I now only use MFJ 1700C switches.

[@piquat1]

Wow, that's a nice switch, especially for MFJ. And it has enough isolation for 2KW. It's almost hard to believe coming from MFJ, but they do have some winners in there along with the duds.

[@Lee_Adamson_OCF]

I've been trying to figure out the most convenient way to multiplex all my rigs between my tuners and all my antennas, too. I ended up settling on an old 19" rackmount panel covered with 50 ohm BNC bulkhead connectors that I found on ebay for $20 or so. I'll connect all the rigs and tuner inputs/outputs and antennas to the back, and then make up a bunch of BNC patch cables to cross-connect stuff on the front.

[@DXCommanderHQ]

Oh nice!

[@M0JHN]

You could mount two switches back into one another so you can switch between rigs and antennas but only have one of each on at a time. You patch panel idea sounds great and way more flexible. I might need to implement this I think.

[@stargazer7644]

That's exactly how I do it too. I don't trust the isolation of those switches. The BNC patch panel allows me to patch any antenna to any rig antenna connector in a moment with excellent isolation. I use SO-239s for 1500 watt connections as the BNCs can't handle that kind of power.

[@edk4590]

Excellent as always Cal. I remember this or somthing very close before Y.T blew it.

[@DXCommanderHQ]

Oh yes!

[@Kake84]

Always finger tight connectors never with tools!!! That 1x2 CX-210 2:54 is very easy to broke too much torque. Over tightening twist that copper strip inside and make center pin grounded on back plate or not connect.

[@DXCommanderHQ]

Every time.

[@timprice1284]

Never thought about the things you showed in video! Good information for sure! 73s ND4A

[@DXCommanderHQ]

Thanks for watching

[@davidfradley12]

be good to see mc kinley on dx comader

[@notepid]

I can understand the reason for grounding the center on the antenna side, but if you do this to switch between radios are you not shortening the output of the radio? That could be really bad for the radio if you accidently transmit while its output is shorted?

[@DXCommanderHQ]

Unlikely with a modern radio..

[@richarde735]

never realized the two position switch shorts to ground in the center position

[@nekotherion7317]

Wonder if any of these, have enough isolation and room to fit relays in a proper way -- and perhaps a Pi pico -- or at least get the control pins for the relays out via some [hopefully weather rated] connector -- very interesting designs though -- wondering if itd be cheaper to just get a few relays, chassis connectors for your radios/antennas, and get a metal project case with a gasket -- wire it all up and then you have a remote antenna/radio switch

[@DXCommanderHQ]

Dunno!

[@ivorbiggen9599]

Thanks for that, just bought a Watson CXSW4PL, should of watched your vid first,, love the vids by the way

[@DXCommanderHQ]

I dond't think it makes much difference on HF :)

[@jeffpetrick4502]

Hey Callum wondering if you ever checked out Diamond coax switch CX-310 (3X1,) German made. Love your videos, I've learned so much from you in a short time. Thanks for everything you do for the Ham community. Jeff AE4WZ Florida, USA

[@DXCommanderHQ]

I've moved away from basic switches since I got the Genius 8x2.. But I seem to remember the CX-310 is a nice one.

[@jeffpetrick4502]

Thank You

[@temporarilyoffline]

So grounding will protect the other radios from the hot TX of the active radio?

[@DXCommanderHQ]

Yes.. Well, that's the idea!

[@rickeaston3228]

Here is something to ponder.....if all shields are connected together and some of the inner conductors are connected to shield, what happens if there is noise or signal on any shield or inner conductor???? Shields are not at RF ground at the switch!!!!!! Signals will travel to active radio via ground wire/shield???? Right???

[@DXCommanderHQ]

Guess so.

[@nogatco1]

Is it possible to turn the inclosure into rca plug ins ?

[@DXCommanderHQ]

Honestly, I don't know. Sorry.

[@JEFF-Elliott]

This design you apparently like is a F***Nightmare. Somehow, the copper strip manages to turn and doesn’t make contact on the other side, so the aerial becomes open circuit and until you’re putting your 100 / 200 watts in and damaged the PA, do you realise that the switch hasn’t worked? 😢

[@DXCommanderHQ]

You need to make them. You would make a fortune.

[@jake30966]

Are switchers band specific or can any one be used ? The Watson CX-SW2PL says its for HF .

[@DXCommanderHQ]

Dunno sorry

[@EmmeTupakoiTaalla]

Hello Callum. Maybe you can some day test the expensive Alpha Delta-4 (for example) switch. I am curious to know is it worth of money. 73 OH1EDK Markku

[@DXCommanderHQ]

Goodness... I don't have one and I don't really review stuff sorry.

[@energy102]

Did you mention how many watts those switches can handle?

[@DXCommanderHQ]

At low SWR, they will all run a lot, I'm sure.

[@applemachome]

I don’t quite understand how that first one works still.

[@johnforte3466]

I love you in a non sexual way. Great vids all the time. Your real approach to ham radio is nice. 73

[@DXCommanderHQ]

FUNNY!

[@wildbill1]

I have the CX 210. Your test shows the connection not grounded compared to the others . Should I get a different switch? I paid about $50 for it. Currently have it connected 2 two radios. But only use one at a time. If it’s not grounded can it cause flashover?

[@DXCommanderHQ]

I don't think it matters.. I wanted to ground due to switching rigs.

[@roseingalsbe6085]

Be careful with hi drive at 1500 watts my rig suffered flash over to my ic736 then it had to go to. The shop 73 n4irs

[@stargazer7644]

None of these switches has anywhere near enough isolation at 1500 watts.

[@poly_hexamethyl]

They're all crap. Bird Coaxwitch is your friend. (Though not your bank account's friend :-) I use a couple of Russian (?) military surplus switches that have DIN 7/16 connectors and, like the Bird, plug and unplug the coax inside the switch. They look like they're built to handle at least 10kW and could survive a tank running over them :-)

[@DXCommanderHQ]

Bird.. Oh yes, top of the range stuff.

[@Py1axRADIOAMADORISMOSEMSTRESS]

CALLING is better when ALL Mash is conectei or better separeted ? I dont use any more antena Key I makes female in coper and only chance in Shack wha antena andvradio Góes for you now what I meen Tony py1ax acostomer

[@anenglishmaninbrazil3212]

LBC so she's the 1 lol

[@benwilliams8596]

vasoline

[@DXCommanderHQ]

Every time!