Posted: 4/5/2012 7:14:19 PM EDT
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I have a Yaesu VX-6R. I am currently storing it without its antenna attached inside a Pelican case with silica gel.
Will constantly taking off and putting on the antenna harm the SMA connector as long as your careful with the threads? Thanks! -HB65 |
| SMA connectors were never designed for a significant number of mate/demate cycles. And worse in an HT, because the center pin is rotating along with the threaded part of the connector. Not that I don't change antennas when I need to, but I wouldn't be removing it constantly. YMMV. |
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Quoted:
SMA connectors were never designed for a significant number of mate/demate cycles. And worse in an HT, because the center pin is rotating along with the threaded part of the connector. Not that I don't change antennas when I need to, but I wouldn't be removing it constantly. YMMV. This. SMA connectors are not designed for large numbers of mate/ demate cycles. A couple hundred cycles is about all they can handle. Optimal performance of the connector is also constrained by proper torque. They actually make a small torque wrench to tighten them. Over torque them and you will significantly reduce the service life and performance of the connector. |
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While it is true that SMAs are not designed for a large number of mate/de-mate cycles, this assumes it is being used to its design limit of 18GHz. At 18GHz the limit is typically 500 cycles. Hence if you mated/de-mated once a week, you'd be good for about 10 years.
More importantly, however, is that in this V/UHF application, i.e. well below 18GHz, you can get away with murder. Pretty much anything short physically breaking the SMA or it's connections and you will be OK. Bottom line: there is nothing to worry about, but don't be rough with it, it is a small connector. |
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Quoted:
Quoted:
SMA connectors were never designed for a significant number of mate/demate cycles. And worse in an HT, because the center pin is rotating along with the threaded part of the connector. Not that I don't change antennas when I need to, but I wouldn't be removing it constantly. YMMV. This. SMA connectors are not designed for large numbers of mate/ demate cycles. A couple hundred cycles is about all they can handle. Optimal performance of the connector is also constrained by proper torque. They actually make a small torque wrench to tighten them. Over torque them and you will significantly reduce the service life and performance of the connector. This ^ ^ ^ ^ ^ I bought an SMA to BNC adapter encased in rubber and added a BNC antenna to my H.T. In my industry experience the SMA connectors don't last very many connection cycles. FWIW Diamond sells something that I haven't actually seen. Finally: SMA to BNC Adapter Scroll down, This is what I have, it's very well done and may be out of print. 73, Rob |
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That adapter is a tradeoff from one weakness to another. Sure, BNC may be easier for quick connect/disconnect, but that rigid adapter exerts leverage on the radio's connector and may shorten the life of the SMA and/or the radio's die cast chassis. If you're using it for the radio's sake, it's counterproductive, IMO. If you're using it because BNC is more convenient for you then you'd be better off with a flexible pigtail made from a few inches of LMR-100.
Then there's also a wee bit of insertion loss and the possibility that the adapter is not constant impedance, but those would be minor issues. The SMA will survive fine for the life of the radio in the OP's situation. |
| I have a FDC HT that has a SMA male on the rasio. I've taken it off and on maybe 500 timesn going from the car using a 40-50 watt amp tyo using it as a HT. No problems yet. Its a tough little HT. Way more substantial than the Wouxans (sp?) The FDC are used as LMR in China. |