14th Jun 2019, 6:18 pm | #21 |
Dekatron
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Re: Save our 2 Metre Band.
I'm surprised your IC-910 doesn't have CTCSS - surely Icom would have designed for world-markets. CTCSS has been the standard access-mode in the US since repeaters started emerging back there in the 60s, and I doubt Icom would knowingly have excluded themselves from the US market by producing a non-CTCSS-capable radio.
As to the developing future of 2M - when we were given access to the 146-147MHz range a few years back, I had sort-of hoped that because there was no extant bandplan it might have triggered the adoption of (and/or experimentation with) some more-modern technologies [spread-spectrum, high-quality digital audio/TV] but this sadly does not seem to have happened. A shame - you can fit good-quality colour TV in a 500KHz bandwidth when using modern CODECs and relatively little processing-power. |
14th Jun 2019, 6:18 pm | #22 |
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Re: Save our 2 Metre Band.
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14th Jun 2019, 6:22 pm | #23 | |
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Re: Save our 2 Metre Band.
Quote:
A lot of people didn't buy the option at the time because it wasn't needed but now that it is, the option is typically no longer available to buy. |
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14th Jun 2019, 6:54 pm | #24 |
Octode
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Re: Save our 2 Metre Band.
The following appears in this weekend's GB2RS News (from their website):
On Monday the 10th of June, IARU Region 1 provided detailed background and serious concerns it has regarding two proposals under discussion in CEPT/Europe that may potentially impact important amateur bands at 144-146MHz and 1240-1300MHz on a global basis if initially adopted and eventually agreed at the 2023 conference. The 2m band has a proposal for a Primary Aeronautical Mobile service allocation, whilst 23cm faces potential restrictions with respect to the European Galileo and similar satellite navigation services. RSGB and IARU volunteers are actively involved with the CEPT meetings and other fora considering these initial proposals. The RSGB’s own special focus page is at https://rsgb.org/wrc-19. Whilst IARU and RSGB wish to draw this information to the attention of the amateur community, we urge restraint in pubic and social media comments until further progress has been made in the regulatory discussions. More details can found at www.iaru-r1.org I think we should note the final paragraph and not get into wild discussions on here (and other forums I have visited). 73 Dave G3YMC |
14th Jun 2019, 7:44 pm | #25 |
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Re: Save our 2 Metre Band.
Well that was a wasted afternoon sharpening all my pitchforks!
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14th Jun 2019, 10:31 pm | #26 | |
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Re: Save our 2 Metre Band.
Quote:
I believe the US model has CTCSS but 1750Hz isn't available in the same box. For a VHF radio that gets pushed towards the £2k mark when fully equipped, I'd expect better. I'd assumed there would be CTCSS, integrated with memories and all that. Anyway, the 2m is far under-utilised. If we lose it many people will be upset, quite a lot will be incensed, but only the few who use it will have actually lost anything.
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15th Jun 2019, 12:16 am | #27 |
Dekatron
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Re: Save our 2 Metre Band.
That's quite awful to be honest. I'd be annoyed. Turns out you can mod it to get CTCSS in Europe though. See: https://www.mods.dk/index.php?ModelI...RadioId=1-icom (you have to create an account and you get one download a day). Madness really. My £55 ML&S "contract fell through" clearance sale FT-25E HT does both CTCSS and 1750Hz out of the box.
Regardless I thought policy was repeaters are supposed to accept 1750Hz anyway still? |
15th Jun 2019, 1:24 am | #28 |
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Re: Save our 2 Metre Band.
I just dug out my old FT290R, blew the dust off it, put it in repeater mode and tried the CALL button on 145.725MHz. This is GB3CG and I think this is in Churchdown near Gloucester. It seemed to work with a 1750Hz tone because the repeater opened and gave a K and a pause. This radio does not have CTCSS. I stopped 'operating' on the 2m band many, many years ago. I've never even used this FT290R for a contact, I bought it as an ebay bargain for about £35 a long time ago when these radios were worth next to nothing. The idea was to sling it in the car as a backup to a mobile phone but I never got around to installing it. It does still seem to work though.
I tried again using my Marconi 2024 sig gen set to a 1750Hz toneburst and +20dBm power and that opened the repeater as well. I then tried setting the 2024 to give a CTCSS tone at 118.8Hz and that worked as well. But I only had to shift this tone a few Hz and the repeater rejected it. I also tried the same on the nearby GB3MH repeater but got nothing for a 1750Hz tone or the required 88.5Hz CTCSS tone. I think this repeater is operational but so far it hasn't popped up with any ID transmissions. In this area there are a few regulars on 2m and there is usually someone calling on S20 every few minutes or so in the late afternoon or very early evening. I don't monitor the local repeaters but when I have looked in the past they always seem to be unused. Such a contrast to the repeater mayhem of 30-35 years ago!
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15th Jun 2019, 2:01 am | #29 |
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Re: Save our 2 Metre Band.
I had a look at the local repeater map and GB3MH isn't a local repeater. I assumed it was MH for Malvern Hills. But it is in East Grinstead! The local repeater that used to be on 145.625MHz was GB3NW but this is listed as being off the air. It looks like it was taken off air a few weeks ago. So no wonder I can't access it or hear any ID transmissions!
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15th Jun 2019, 8:26 am | #30 | |
Heptode
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Re: Save our 2 Metre Band.
Quote:
I've been saying this for years and people keep denying it. its refreshing to hear others think the same. I have never had it convincingly explained why we cannot drop the ctcss requirement. It's killed repeater use. It's Killed mobile use. It's killed 2m use.
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15th Jun 2019, 8:51 am | #31 |
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Re: Save our 2 Metre Band.
Who's idea was CTCSS?
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15th Jun 2019, 9:20 am | #32 |
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Re: Save our 2 Metre Band.
The reasoning given at the time was that CTCSS would prevent a distant co-channel repeater being opened at the same time as the intended box.
Methinks that if this had been a major problem people would be saying "Thank heavens for CTCSS saving the planet from terrible repeater doubling!" but instead people are asking what it's for. This might just be a clue to its necessity. As amateur radio is desperate for new recruits, and the RSGB desperate for new members, reverting to 1750Hz access and having a mixture of 25kHz and 12.5kHz channels in the band plans could put a lot of gear back on the air at no cost in these austere times, and might give a needed boost to activity. It looks like we may need that boost to be able to keep the band. David
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15th Jun 2019, 9:47 am | #33 |
Nonode
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Re: Save our 2 Metre Band.
Some of the ground radio I used to repair was 108 -154.975 in the original spec. and was tested as such.
Back when I used (1750 tone access) repeaters and a rig without a toneburst, I could quite accurately whistle 1750 to open it. Rob
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15th Jun 2019, 10:00 am | #34 |
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Re: Save our 2 Metre Band.
Thanks David.
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15th Jun 2019, 10:26 am | #35 |
Pentode
Join Date: Jun 2018
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Re: Save our 2 Metre Band.
The analogue voice repeaters run by the Central Scotland F.M Group all can be opened with 1750Hz tone, so round these parts there was never any need to ditch your old boat anchor and upgrade to a new rig with CTCSS, so that really does not count for the lack of activity here.
Activity is lower here than it was back in the day, but there is usually some traffic. Paisley 2m repeater can be well used during the day, and the Kilsyth 70Cm repeater is a good natter box. This week I have had quite a number of QSO's on both 2 & 70 simplex. Still no where near the traffic as seen in the past though.
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15th Jun 2019, 11:16 am | #36 |
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Re: Save our 2 Metre Band.
2m has far too many channels and not enough frequencies. If I want to go on the air I have to look up a long list of channels I need to avoid, even though almost all of them are empty. I regard them in the same way as bus lanes: I respect them but find them deeply annoying.
Much more fun back in the days before channels. I had a couple of crystals in my own geographical zone. People would find me; I would find them. I used FM, but was happy to chat to someone transmitting AM or sideband. I realise that those days are gone, but we could improve 2m by cutting back on all the empty channels. It baffles me why there are 2 or 3 incompatible digital voice modes. Now I hear that digital non-voice modes seem to be multiplying too. |
15th Jun 2019, 1:14 pm | #37 |
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Re: Save our 2 Metre Band.
Competing commercial interests. We need that in Amateur Radio, don't we(?)
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15th Jun 2019, 1:33 pm | #38 |
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Re: Save our 2 Metre Band.
Hopefully, it's a replay of quadrophonics, they all lose and we go back to straight analogue!
David
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17th Jun 2019, 8:59 am | #39 |
Dekatron
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Re: Save our 2 Metre Band.
For those against the idea of CTCSS altogether, what about all those lovely CTCSS equipped ex-PMR sets and cheap Chinese made handsets and mobiles which have never heard of 1750Hz toneburst?
Granted, you can build a little 1750Hz toneburst generator and build it into the radio or the microphone, but why bother if both the radio and the repeater support CTCSS? The best, most flexible situation is for repeaters to support both access methods. The wholly unnecessary introduction of digital transmissions on previously analogue only frequencies annoys me a lot more, nowadays it's impossible to scan the R / RB repeater output frequencies without being hit with a wall of digital noise at some point. |
18th Jun 2019, 9:29 am | #40 |
Heptode
Join Date: May 2008
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Re: Save our 2 Metre Band.
I don't think the problem is so much the use of CTCSS in itself, but the use of different CTCSS tones for different repeaters. The repeaters are already frequency co-ordinated to provide separation, so the only issues come about during periods of enhanced propagation, and then we all used to love the fun that provided!
Now, unless you have a copy of the allocation table, or internet access, or are lucky enough to hear the repeater ID and catch the single morse letter at the end denoting the required tone (and of course either know for are able to look up which tone that letter is!) then working with any even slightly unfamiliar repeater is near impossible. So, you end up with all your radio memories filled with every combination of frequency and tone, and have to try them all out! Utterly pointless and frustrating. Go back to 1750Hz toneburst and/or a single country side CTCSS tone!
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