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VHF handhelds that are less susceptible to intermod/overload?

Mostly I prefer HF CW for my SOTA activations, but am recently giving VHF a try as I can get into the large population centres of from Vancouver through to Seattle from our island.

In my neck of the woods (VE7/CL) many of the nearby summits have commercial radio towers on them. I have noted my el cheapo Wouxun UVD1P receiver got completely overloaded once from the local RF at one summit as to be almost unusable. Many years ago an older Kenwood handheld had similar problems when I activated from a large hilltop with commercial radio towers nearby (well before SOTA even began). At that time it was the priciest Kenwood handheld on the market.

I may have access to an older Motorola HT1250 handheld and wonder whether it might be worth reprogramming this for amateur frequencies - hoping they might be a bit more robust on the receiver front-end ??

Has anyone out there found a really good handheld that does not suffer so much from such problems?

73’s Larry VE7EA

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Two thoughts for VHF/UHF on summits with lots of RF activity.

First - Hike to the summit then back down to the low end of the Activation Zone - being in the AZ but below the commercial/cell/ham repeaters may be all that you need to do. You will not get the 360 degree view and contacts, but you may be able to hear the stations calling you.

Second - Use a minimum antenna - the original rubber ducky that came with the HT rather than the extended rubber ducky. Less antenna will capture less RF interference. This is like using the attenuator on your HF rig. Save the roll-up j-pole for sites with no RF problems.

A surprising number of hams still use the old Radio Shack (Tandy) HTX-202.
The story that I heard was that they have a band-pass filter built into the radio to prevent modifications to allow out-of-band use.
Ian

The older the model, the more likely it is that it has a filter of some kind in the input circuitry. Those that advertise wide band coverage of the entire vhf uhf spectrum have very little filtering so are most susceptible to front end or mixer overload.
All that said, there are low pass filters on ebay with a cutoff around 180 mhz, have seen only SMA connectors on them, or there are home brew filter designs I have posted before, so you can use BNC or other connectors to suit your rig.
Some have found the FT817 survives the high VHF RF environment better than the HTs do. My ICom V85 survives better than most of the Yaesu general coverage rigs, but every batch of every radio in every marketplace appears to be slightly different so it is very difficult to draw conclusions with any certainty. The old icom mobile (IC22A and IC22S 10w) had helical filters in the front end which is far better than any HT I know of.

Another option is to use horizontal polarisation if you are doing HT-to_HT S2S contacts. That may give better signals on 146 and reduce the signal level from the QRM sources. Again, very difficult to generalise even from specific successes found here.
Good luck.

73 Andrew VK1DA/VK2UH

I can confirm the FT817 story. Quite recently I tried to make a 2m S2S QSO to another activator with my FT1XD, made a few calls but heard nothing back. After a while I connected the same handheld antenna to the front connector of my FT817 and had no problem making a contact. They told me that they heard me before with very good signal and wondered why I didn’t answer.
Same antenna, both 5W. Both radios are proven to work ok.
Needless to say, there is a huge comms tower and a number of smaller ones on that hill.

Razvan has already produced an excellent article about this.

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Reduce the attenuation either within the programming of the radio OR using a shorter antenna. Sometimes I will use a second handheld with a shorter antenna to “receive” and use my primary radio to transmit.

Use a nearby building to “block” the RF. Get on the side furthest side of the building away from the antennas. Get low to the ground.

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In another thread, I posted about my search for the perfect 2m SOTA radio. Here is part of the info copied from that thread:

Rather than resort to a crummy antenna, I went with a better radio. I spent months testing various radios from friends on my bench for overload and intermod rejection. Discovered that the Icom IC-2A and the Radio Shack HTX-202 had the best receivers of all, including new HTs.

I bought a few mint condition of each and set about making them 100% before going to any summits. I have been to several densely populated tower sites with them (I work in broadcasting, so I am at a tower almost every day) and confirmed that the Radio Shack HTX-202 and the Icom IC-2A have no trouble even in the strongest fields with other VHF gear.

Nothing worse that hearing someone call “CQ SOTA” over and over and them not hearing the dozens of stations trying to come back to them on their Baofeng HT!