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Do commercial radio transmitters make your HT deaf?

I recently got a Yaesu VX-6 in high hopes it would be able to work on summits
even when commercial radio transmitters are near (common situation).
But I was very disappointed to see it actually performs worse than my previous
HT (Wouxun UV6D).

With Wouxun, it’s squelch would stay open regardless of level (say SQL 9) and I would
constantly hear noise, but when someone called, it was usually able to pick up the FM
and I was able to hear the caller clearly.

The Yaesu becomes as deaf as a brick on 2m and the squelch will not open even
when it’s set to 1. There were at least 5 stations calling me and I wasn’t able to
hear a single one! When I set squelch to 0, I was able to hear the noise but no
stations, it simply would not decode any FM.

Finally, I turned on the front end attenuator (menu) and I was able to pick up some
nearby stations. They were much weaker (as expected), S1 to S5 on the meter
(where they would normally be S9+, but at least I was able to hear them and they
would open my squelch).

Does anyone have similar experience? I got the Yeasu because I had heard all the
praises about it’s resilience, but this is rather sad. I’ve had it for several weeks now and
it works perfectly when transmitter towers are not near.

Could the reason be that the transmitter (commercial VHF) could be messing with my
radio’s intermediate stage?

Blocking due to co-located transmitters (or sometime even distant ones) is a very common occurrence. I was listening to a SOTA station near hear today on a hill with many transmitters (Winter Hill) who could not hear many of the stations calling him. Tilting the radio so that the antenna is horizontal sometimes helps.

With almost all modern HTs, yes. One solution is to add a low pass filter to the antenna connection, ie, filter connects to the radio, antenna connects to the filter. In an earlier thread (use search option above) I posted a copy of an article about suitable filters.

This solution works if the commercial/broadcasting services causing the problem are higher in frequency than the 2m band. They usually are.

Some activators avoid using 2m fm at a site known to have such problems, and use hf there.

73 Andrew VK1DA/VK2UH

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Hi Jakub, The Yaesu VX-6R has a wide band receiver (504 kHz to 998.99 MHz.) which while often very useful for listening to other frequencies does mean that the receiver can be desensed by local transmitters on ANY frequency!

It is interested that your old Wouxon has less of a problem as it also has a wide band receiver (often 110-174MHz for example) but of course that’s not as wide as the Yaesu and if the local transmitter is perhaps on 800MHz it probably wouldn’t affect the Wouxon but could affect the Yaesu. The ideal HT would be one with just 144-148 recieve. Most HTs nowadays cover Air band through 174MHz though. iCOM are also wide band. I’m not sure about Kenwood or Alinco etc.

If you were to have a portable beam antenna, this might help somewaht as it would act to an extent as a band pass filter.

73 Ed.

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Thank you Ed, first of all thanks for all the QSOs from my SOTA activations, I count 12! :slight_smile: And then, as far as I understand, VX-6 has 2 receivers and only the secondary is wide band, so the primary should be good to go.

The problem is, we have tested a Yaesu FT60, Wouxun UV1D next to my Yaesu VX-6. Same antenna, same place. No stations opened my squelch even stations that were 59+20dB on the FT60 and Wouxun. I am considering returning it, I’ve been only using it for 1 month and the results are terrible.

I agree, for the reasonable purpose you have for the HT, it is not performing as it should. I would also return it for a refund or replacement with a HT that will work better in a High RF environment. Any HT is going to be affected to some extent but it sounds like the VX-6R is particularly poor in this respect.

I hadn’t realised the VX-6R has two receivers - I just looked at the brochure online it it stated that it has a wideband receiver. In any case, you have proved that even the narrow band receiver is being badly desensed.

73 Ed.

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By the way, I’m probably going to return or sell the Yaesu, any tips on something that’s really good even in intensive em fields? I used to have a Wouxun UV6D which was…well not the best, but at least better than the Yaesu. Do you think there is anything better? (current models)

The Yaesu FT-70D works well in close proximity to commercial hilltop sites according to Tom @M1EYP. That gives you a dual band FM handy and Yaesu’s digital voice modes for a reasonable price.

The FT60 was a brilliant handheld, very good in strong RF fields. Your Wouxun was one of the better models they sold.

The Yaesu VX170 was an amateur version of a commercial market Yaesu radio. Waterproof and bulletproof on RF. Battery lasts for ever, audio is loud, very well made. 2m only. It’s replacement the FT-230r was just as capable. No longer sold. Both are worth seeking out second hand.

There must be new handhelds from Kenwood, Icom that work well but I don’t know of any. I do know the old (maybe 20+ years old now) Kenwood TH79 is an excellent dual band handheld. Feels and looks good and works well by other transmitters. I have only ever seen 2 for sale in the last 10 years.

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The VX-7 has two receivers, but I thought they were both wideband. I think you can listen to any band on either receiver.

The VX-6 does not offer dual-receive.

wunder

I was always told that single-band radios would perform better than dual-band (or wide-band) radios in high RF areas.

My personal experiences on various summits seem to validate this theory.

I have a Yaesu VX-8, which struggles on summits with commercial masts. My Icom IC-E92D fairs a little better but still seems to be fairly susceptible. Despite this it is my radio of choice (reasonable battery life, allegedly waterproof and not too heavy). The Icom goes with me on virtually all activations. Both are duel-band with wide-band receivers.

If I know that it’s going to be a bad summit for QRM, I will often take my old Kenwood TH-K2, which is a VHF only radio (136-174) which seems to be really quite immune to all but the worst interference. The catch is that it seems to absolutely eat it’s way through batteries.

If I want something that has a virtually bomb-proof receiver & I’m feeling a bit retro, I’ll take the Yaesu FT-290R. It’s only 2.5 watts but the batteries seem to last forever (I think I’ve changed them twice in the ten years or so that I’ve owned it). Unfortunately it’s definitely not waterproof and it’s damn heavy, so I only take it on summits with a short walk in good weather. It also has the advantage of offering SSB and CW modes if that’s your thing.

In terms of HF, I use an Icom IC-703 but that’s a bit of a digression off topic because we seem to be specifically discussing VHF hand-held radios.

Good luck with ANYTHING made in this century. THE RDA1846 & similar DSP chip seems to have taken over the HT market. My experience with anything SDR in the sort of price range us cheap SOB’s are prepared to pay is that they are great - until they are not! When one exceeds the limited dynamic range of these low-end DSP chips, we’re not talking the occasional sproggy - more like total meltdown.

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Hello,
I also have VX-6 and like it alot!
I had an issue filter problem with it, deft! This is (normal) in some VX-6 / 7 (you can go to menu and change the filter to wide, but no worth it…)
Sent to Yaesu and they replace the filter and now is one of the best HT i have!
Here you can see the (thing): http://pages.cs.wisc.edu/~timc/e/vx7r.html

I hope this help.

73
José
CT2HTY

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Thanks José, did that happen to the station which was brand new? (as in my case)

No Jakub, mine was bought in second hand, but developed that issue months later.
If yours is brand new, you have the warranty! :wink:

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Thanks I have already contaced the seller.

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I’ve had issues in the past with pager transmitters blasting out very strong signals around 150MHz. I’ve noticed it particularly when connecting cheap handhelds to larger aerials.
Pager traffic has a fairly low duty cycle though, so a little different to what you’re describing.