Hand Held HT's and RFI - The Sotabeams band pass filter

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  • Опубликовано: 22 ноя 2024

Комментарии • 62

  • @davidcameron4614
    @davidcameron4614 Год назад +1

    This is why repeaters that have to listen for the weakest of signals in the highest of RF fields have significant front end filtering. The issue is without the filter in front, the receiver amplifier in the radio gets saturated with RF, and generates its own mixes of multiple signals, and that is what you are hearing. The reason why the FT-60 is best is that it likely has lower receiver amplifier gain. But proper monoband radios will have a helical front end to limit the RF into the receiver. For example, the Motorola Quantar has a 6-pole VHF bandpass filter built into the chassis. It passes about 2MHz of spectrum, and sharply rolls off anything else. Signals only 1MHz above and below the passband are cut in 1/10th or so (10dB), and the further from the passband, the more attenuated they are.

    • @theradiorover
      @theradiorover  Год назад

      Absolutely. Then compare that with the plethora of Chinese "radio on a chip" offerings and you can see why they don't stand up. Although I haven't checked the circuits of my ft-3d, I would have to assume it is a similar issue, given that the device is a traditional FM transceiver, GPS, QSO recorder, analogue APRS, YSF digital mode etc.

  • @feltusfeicit
    @feltusfeicit 5 месяцев назад

    Thank you for that! I had amusing difficulty on one of my very first summits when I was next to a doppler installation. So I got a filter, and took a few radios up a summit that had 3 towers. Amusingly my VX-7R and Anytone 878 UV II+ had no issues without the filter, but the older Alinco I had with me received absolutely nothing, and I had the same issue of forgetting the right antenna adapter for the filter.

    • @theradiorover
      @theradiorover  5 месяцев назад

      All part of the fun! Learning from your experiences and mistakes, and I've made planty of them. Thanks for sharing.
      Fraser MM0EFI

  • @richardpowell723
    @richardpowell723 Год назад +3

    A great experiment, which shows limitations of HT radios and potential solutions for extending their use ability.
    I too have a VX7R. And a VX5R! Replacement batteries are still available…
    Thank you for another superb video.
    M0DSK

    • @theradiorover
      @theradiorover  Год назад +1

      I managed to get a new non-yaesu battery for vx7. I need to see if it has an internal button cell as it doesn't retain the clock time any more. The vx5 is a great radio too. It's a shame the ft3d has short comings, as the aprs function is very handy.
      73, Fraser MM0EFI

    • @richardpowell723
      @richardpowell723 Год назад +1

      @@theradiorover I think the Yaesu battery is still available. Either way we can continue to get extended use from our investments. And the radio hobby becomes cost effective at that point. 👍

    • @nine7295
      @nine7295 Год назад +1

      I have 2 7R and 1 5R (which is my second one). One of the 2 7Rs is a part radio now, as it was damaged by being run over by a car .

  • @wa7jnjradio
    @wa7jnjradio Год назад

    Great video, and fun to see the comparisons. I've experience so many more interference issues using the FT3D on a summit, and didn't have quite as many with the FT70. Forgot to pack the SOTABEAMS band pass filter on a recent summit, and definitely missed having it due to interference (even with no towers on summit). 73, James

    • @theradiorover
      @theradiorover  Год назад +1

      James, I was using my ft3d with SOTA filter the other day with good results. The summit station I worked asked me for a QSO on 70cm, so up I went. Couldn't hear them at all.
      Then I realised the filter was still in line 🙄.

  • @JeffCowan
    @JeffCowan Год назад +2

    This is exactly relevant to my current interests as we have quite a few hills here with serious RF interference. A friend has had decent luck with his FT-60 in rough conditions.

    • @theradiorover
      @theradiorover  Год назад +1

      Jeff, the ft-60 does the job nicely. I prefer the vx7 because it is more weatherproof, however things like squelch need to be accessed through the menu, which isn't so handy, as I like to open the squelch right up when operating and then close it when I'm mobile. The ft3d was the real disappointment though...
      73, Fraser MM0EFI

  • @brucecairnie3975
    @brucecairnie3975 Год назад

    I carry my FT-60 with me on SOTA activations and leave the FT-2D behind. The 60 is solid, can be dropped in the cold, and does well with its batteries. What’s more, I find it works very well for me in the 2m activations that I try - IO get good reports and have no trouble hearing, even when the wind is blowing hard. I use it with an MFJ LongRanger, a Diamond SR77CA and my 4 element Arrow Yagi. Thanks for the video and 73, VA7SGY (born in Aberdeen)

    • @theradiorover
      @theradiorover  Год назад

      Hi Bruce, Great to hear that. The other great thing is because it it a yaesu, you can still get spare batteries for them.
      73 from Aberdeenshire.
      Fraser MM0EFI

  • @acestudioscouk-Ace-G0ACE
    @acestudioscouk-Ace-G0ACE 11 месяцев назад

    Interesting, thanks to both of your for this.

    • @theradiorover
      @theradiorover  11 месяцев назад

      Glad you found it useful!
      73, Fraser MM0EFI

  • @m0kov
    @m0kov Год назад

    After a lot of deliberations, this is why I chose to buy an Icom ic-v80. It's a 2m single band with no extras, so it won't appeal to everybody, but has a good superhet receiver. I believe that most of the cheap dual banders have direct conversion receivers and fairly wide-open front ends. So far, the Icom has performed well, only downsize for me, is its weight.
    Frazer, great RUclips channel, thanks for taking the time to upload all these interesting videos and hope to catch you sometime on the bands.
    73 Steve M0KOV

    • @theradiorover
      @theradiorover  Год назад +1

      Steve, That sounds like a really sensible purchase. The problem with the yaesu ft-3d is that it is trying to be a radio, GPS, APRS node, record tx, rx and also do digi-modes. That doesn't leave a lot of room for the radio bits!
      Glad you're enjoying the Channel. Thanks for your support.
      73, Fraser MM0EFI

  • @M0RSF
    @M0RSF Год назад +1

    Interesting video Fraser. I find the RX audio on my Yaesu FT3D to lack any bass. Also using my Yaesu VX7R in the house to monitor local stations and repeaters I can hear stations that I can't hear on my FT3D. Hopefully we will have a VX7R S2S sometime. 73 Chris M0RSF

    • @theradiorover
      @theradiorover  Год назад

      Sounds good Chris. The VX7R is a cracking radio.

  • @JohnUsp
    @JohnUsp Год назад

    Excellent experiment, thanks. When I do my tests, I always select a repeater with a frequency close to 146.520 and a very weak signal, weaker is better and Baofeng fails to receive, and Icom, Yaesu, Kenwood receive fine.

    • @theradiorover
      @theradiorover  Год назад +1

      Great tip! We can't use 146 Mhz in Europe, but I get what you mean. In some ways I made the test too easy by using a local station. Someone on a hill with an HT maybe 30 miles away would have really shown which one had the best RX.
      73, Fraser MM0EFI

  • @PaulC-2M0YZT
    @PaulC-2M0YZT Год назад

    Brimmond Hill remember it well as a kid with the big offshore dishes. Not been up there for years.

    • @theradiorover
      @theradiorover  Год назад

      No big dishes up there now. I guess tech has improved over the years. The huge microwave dishes on Mormond Hill near Fraserburgh are gone too! It's a nice spot on Brimond Hill. Funnily enough I had the place to myself that day, despite it being a Saturday.
      73, Fraser MM0EFI

  • @IrishHamRadio
    @IrishHamRadio Год назад

    I can’t believe the beautiful audio on that VX-7R! 😮
    I had the same test planned, so I bought a filter, then went to the summit and realised I had the wrong gender adapter 😢…
    Later that week, drove an hour to buy the correct adapter…. A few weeks later went to summit again…. Couldn’t find the adapter in my kit box!!! 😢😢
    Some day Ill get brains Fraser… Some day…. 😅

    • @theradiorover
      @theradiorover  Год назад +1

      Ha! That's why we're amateurs Dave! Chris @M0RSF has a vx7r as well. He loves it. I took it out on Sunday and had 14 2 m contacts. One was 129 miles. Then a guy asked me to ping his new APRS i-gate that he'd built at home. I wasn't able to, as the ft3d was at home!!

    • @IrishHamRadio
      @IrishHamRadio Год назад

      @@theradiorover 😬 the one time you’re actually asked! That doesn’t bode well for the 7R taking first choice on your activations 😜

    • @theradiorover
      @theradiorover  Год назад

      @@IrishHamRadio I guess I'll have to take them both! My pack will be getting as heavy as yours 😂

  • @nine7295
    @nine7295 Год назад

    You said the FT-60R was a museum piece . So what about the VX-7R? The VX-7R came out before the FT-60R! (I own 2 VX-7R, the first time bought when it came out. So i know it well.).

    • @theradiorover
      @theradiorover  Год назад

      HA! Yes, the vx-7r is a classic, isn't it?

  • @PortableRadio
    @PortableRadio Год назад

    Thanks for the experiment Fraser! On some HB9 summits they run pager (POCSAC) just 1 MHz above 2m. You get completely blocked out, even when you're a km away. I guess, in this case the band pass filter will not be of much help neither. Good to have HF for these rare cases 😃.
    73 Stephan

    • @theradiorover
      @theradiorover  Год назад +1

      It is crazy that pagers still exist! I thought that was 1980's tech. Pagers are around 155 MHz in the UK if I recall correctly.
      Thanks for the S2S the other day. Nice to hear your voice in the pileup!
      73, Fraser MM0EFI

    • @PortableRadio
      @PortableRadio Год назад +1

      @@theradiorover Hi Fraser, my comment got probably deleted by the "clever" Google AI.
      My shortened previous comment was that pagers here in HB9 are still in use because they work even down in bunkers, that we have plenty of 😆.
      And thanks for the S2S as well! When I was on HB/FR-028, I had HF RFI from at least 7 other activators around me!
      73 Stephan

    • @theradiorover
      @theradiorover  Год назад

      @@PortableRadio was there a Swiss SOTA event on that day?

    • @PortableRadio
      @PortableRadio Год назад

      @@theradiorover Correct, it was the HB9SOTA snowshoe event. On SOTLAS HB/FR-028 I posted a photo (GoPro Screenshot) where you can see the remaining snow, but to be honest, when the wind was not blowing, it almost felt like spring 🌞

  • @davidgardiner3439
    @davidgardiner3439 Год назад

    I use FT3D for SOTA with Sotabeams filter if needed and got exactly same results as you on summits with comms masts. I’m surprised an expensive rig doesn’t perform a bit better than the cheap ones. Dave Ei3ixb

    • @theradiorover
      @theradiorover  Год назад +1

      Dave, they packed so much into that radio - touchscreen, GPS, APRS, YSF etc that I guess something had to give. They skimped in the filtering and on the speaker. It's a shame really because it is a great bit of kit.
      73, Fraser MM0EFI

  • @DARTHDANSAN
    @DARTHDANSAN Год назад

    Nice . I have a ton UV5Rs and the ftd5r

    • @theradiorover
      @theradiorover  Год назад

      Nice. How is the FT5DR? I wonder if it has a better front end filter...

    • @DARTHDANSAN
      @DARTHDANSAN Год назад

      @@theradiorover I’m not sure if my original reply went through . To sum ftd5r is really confusing to use . The APRS is supper neat . The battery life is ok but the battery’s for ftd5r are way to expensive. I love the simplicity of of the UV5R and the extended 3800 mah battery last for ever . I like being able to unlcock the UV5R for what ever frequency I want . To sum it I find myself using my UV5R a lot more to due better battery life and ease of use

    • @theradiorover
      @theradiorover  Год назад +1

      @@DARTHDANSAN that's interesting. I'm thinking of carrying the ft3d on my rucksack strap when I'm in APRS range and also carrying the VX7r to use for the activation, but that's maybe overkill!

    • @DARTHDANSAN
      @DARTHDANSAN Год назад

      @@theradiorover have you consider the pico APRS v4 for APRS . It’s neat . I have version three and find myself using that more to send APRS messages for fun . The more I think about it the harder of time I have justfiy keeping ftd5r . I have not been able to make to many contacts even though I live a big city . I have my gmrs radio and there is a lot people on there but I couldn’t figure out how to get to connect to the repeater . I just got ft891 and have no clue how to power it or how to get an antenna but I look forward to getting a lot more use out ft891 on hf and I’m working hard to upgrade to general

    • @theradiorover
      @theradiorover  Год назад

      @@DARTHDANSAN to be honest, there's not much APRS around my way, as I live in a rural area. I had to build an APRS repeater just to have something for the ft3d to speak to when I'm on local summits!
      As for your ft-891, any mains powered 12 v (13.8v) power supply should power that, or a lead acid car battery. Use a LiFePO4 (I think Bioenno are available in USA) if going portabe with it. For an antenna, simple dipole, or End Fed half wave with a 49:1 transform will get you going.

  • @excossack
    @excossack Год назад

    Good experiment/testing session. I wonder how the FT857 would perform? I had the same issues activating Snaefell last year. People could hear me but i could not hear then.

    • @theradiorover
      @theradiorover  Год назад

      I suspect the 857 would be fine due to having much better front end filtering. I've used mine on a couple of summits with towers without issue.
      73, Fraser MM0EFI

  • @TomR459
    @TomR459 Год назад

    interference sounds like higher baud pocsag or maybe flex transmissions

    • @theradiorover
      @theradiorover  Год назад +1

      Yes, there's definitely paging in there. IIRC they are at 156 Mhz in the UK.

    • @TomR459
      @TomR459 Год назад +1

      @@theradiorover here in aus they are slightly more annoying at just above 2m on 148mhz

    • @theradiorover
      @theradiorover  Год назад

      @@TomR459 There are 78 SOTA summits in Eastern Scotland (GM/ES). Only five have comms. towers and Brimmond Hill is by far the worst. It is within the city of Aberdeen, near the airport and of course Aberdeen has a lot of comms, for the of shore North Sea oil industry.
      The amusing part is, it's one of the few summits where I can reliably make 2 m contacts. Almost everywhere else is too remote, ie no people. I guess similar in Aus!
      73, Fraser MM0EFI

  • @THESPORTINGCAMP
    @THESPORTINGCAMP Год назад

    73’ de W5SWX

  • @m1hax
    @m1hax Год назад

    Power lines and three masts 😂😂

    • @theradiorover
      @theradiorover  Год назад

      I know! It's an RFI riot. All for a point too. 🤣

  • @ShowAnNDTeLL
    @ShowAnNDTeLL Год назад

    if it was a baofeng you will have crazy rfi

    • @theradiorover
      @theradiorover  Год назад

      Well the Baofeng did OK with the stock whip. I stupidly forgot to bring the convertor for the big antenna because I forgot the baofeng has the opposite to the yaesu. The results wouldn't have been great. The ft3d was poor and that costs 10 times the baofeng!
      73, Fraser MM0EFI

  • @andrewd4890
    @andrewd4890 Год назад

    Consistent with other testing done all over the world at sites with high power VHF transmitters. The older radios had bandpass filters in the early stages of the receiver and were better able to reduce the strength of the out of band signals. The modern radios (FT3D typical) have such a wide range of tuning that to allow them that range, the radios just don’t have the filtering of the older designs. A tradeoff between wide band coverage and receiver performance on the frequencies you actually need. A good test. I don’t know what possessed Baofeng to put a plug onto a radio as an antenna terminal. Radios should have sockets for the antenna, not plugs. Same comment for Anytone. 73 Andrew VK1DA/VK2DA

    • @theradiorover
      @theradiorover  Год назад

      That's a good point about wide band receive, although I think the VX7-R also has this. The FT3-D has so much tech. in a small package. I'd accept a larger radio with band pass filtering for the amateur bands, which are the only ones which the radio can tx anyway, so surely a priority.

    • @nine7295
      @nine7295 Год назад

      What possessed Baofeng? Have you seen a Motorola or Kenwood land mobile hand held? They all have SMA-F on the radio side just the Baofeng , with the Motorola a bit deeper though . Many other brands also use SMA-F on the radio side. Even some Japanese ham HTs have SMA-F, like the Yaesu FT-10R and 40R. Baofengs are far from alone in this.

  • @JohnTarbox
    @JohnTarbox Год назад +1

    Be careful. That filter is only rated for 2 Watts continuous. An HT running APRS could easily exceed that rating.
    Will you be trying some other filters to see if they perform any better? DE WA1KLI

    • @theradiorover
      @theradiorover  Год назад

      Hi John, I do need to be careful with the duty cycle of the filter, that's for sure. I don't think APRS would be an issue, as that is a very short data burst every couple of minutes. TBH I was probably talking for longer in this video that I would be if working SOTA chasers. I guess the air temperature of -2°C helped keep it cool as well.
      All the Best, Fraser MM0EFI