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Handheld with a PL-259 dummy load still transmits 10+ yards


WRQV528
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I recently bought a 100W PL-259 male dummy load that I wish to connect to a Baofeng UV-5R Plus, which is SMA male, using the necessary adapter.

From left to right, a Baofeng UV-5R Plus, an SMA female to PL-259 female adapter, and the dummy load in question, lay on a table.

When testing the dummy load at 1W on GMRS channels, the transmission can be received crystal clear at 10 yards line-of-sight (and likely extends farther than that). Removing the dummy load and transmitting without an antenna yields the same results.

I'm confused... I know a dummy load doesn't completely absorb or dampen all the RF that's pumped into it, but is it really typical for a transmission to still go that far? Have I chosen the wrong dummy load for this radio? Is the dummy load defective? I notice the SMA female side of the adapter is not flush with the entire SMA male connector on the UV-5R as it does with an antenna... is RF escaping from this gap?

A close-up of the gap that exists between the adapter and the UV-5R Plus when screwed together.

Edited by WRQV528
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I notice the SMA female side of the adapter is not flush with the entire SMA male connector on the UV-5R as it does with an antenna... is RF escaping from this gap?

In a word, no.

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I'm confused... I know a dummy load doesn't completely absorb or dampen all the RF that's pumped into it, but is it really typical for a transmission to still go that far?

funny story about that. I was tuning up a new channel for a customer on the bench (late 80's crystal TCXO) as they took some time to settle and the deviation had to be set also. radio is into a 100W dummy and was testing Dev on service monitor , boss gets a call that they are hearing everything I'm doing at the base 7 miles away.

go figure.

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27 minutes ago, WRQV528 said:

Huh. I thought one of the purposes of a dummy load was to prevent interference, especially at that far of a distance. Is there a device that accomplishes this?

Yes, it's called Faraday Cage.

It is very difficult to fully prevent cables, body of the radio, grounding wires, your body, from radiating. The higher the frequency the harder the task. On UHF it is usually solved with a massive (and expensive) common mode current choke on the cable.

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Huh. I thought one of the purposes of a dummy load was to prevent interference, especially at that far of a distance. Is there a device that accomplishes this?

remote base site @300' haat, we practically looked at it.

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Yes, it's called Faraday Cage.

It is very difficult to fully prevent cables, body of the radio, grounding wires, your body, from radiating. The higher the frequency the harder the task.

it was an open 20W 800Mc radio. we have never had a faraday cage at the shop. I did do work for a guy who had a nice one though. converted a small walk in freezer w/ grounded coper screen on the full interior and door. mostly did beepers.

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