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  • Ots's Avatar
    Today, 00:55
    Ots replied to a thread Tuning in Yaesu
    I'm not new to forums and there's a recognizable trend taking place so I've politely bowed out. I thanked everyone for their responses.
    14 replies | 456 view(s)
  • AndyG0CCX's Avatar
    Yesterday, 22:53
    Our local 70cm repeater certainly isn't inhabited by a clique. Sure there are times when no-one is about but most times I can make a call and get a response. There are a few locals who are regulars, but it's quite normal to chat to someone who's 'new', or just passing through the area. When I had the 2m collinear up (and the 'Slim Jim' before that one, for that matter), I could access several of the South East's 2m repeaters and there were plenty of users then. I can hear them now when I'm mobile, but not enough TX power to reach the further ones, and although quieter, they can get pretty busy and there seems to be none of the 'I don't know you so I'm not talking to you.' attitude. Could it be that we're just more open over here, or more polite to our fellow hams? I don't know the answer to that one!
    11 replies | 135 view(s)
  • WZ7U's Avatar
    Yesterday, 21:22
    Aren't you ever out of the "get off my lawn" mode?
    11 replies | 135 view(s)
  • WZ7U's Avatar
    Yesterday, 20:31
    WZ7U replied to a thread Mobile Radios IC706MK11G Won't Key in CW Mode in Icom
    Fantastic! I'm glad it was an easy fix. Go enjoy that 20 year old tech, just don't forget the finals are not available. Always present a suitable load to it and it will be happy. Have fun, good hunting!
    3 replies | 98 view(s)
  • camerart's Avatar
    Yesterday, 17:57
    Hi P, Ok, thanks, I'll give it away. C.
    6 replies | 102 view(s)
  • camerart's Avatar
    Yesterday, 17:54
    Hi S, Ok, thanks. I'm a fan of low power. I've just ordered a handheld Beofang. Using a friends, I've got into this repeater with it. Let's see if it works from here? C.
    6 replies | 102 view(s)
  • paulears's Avatar
    Yesterday, 17:21
    Look at the design. The usual limit for two waves, or a wave and a wave, for example is about 3dBd - less a bit of matching loss - which is what these adjustments do. They cannot add gain, this is a function of the total design. Realistically, to get another 3dBd, the effective length of the antenna needs to double. If it was a case of tweaking the coupling screws, Diaond would have done it, claimed extra gain and increased the price. Like sixmeters says, you're expecting too much.
    6 replies | 102 view(s)
  • Sixmeters's Avatar
    Yesterday, 17:11
    You are asking too much from the Diamond V-2000 antenna.. The two variables are the coax you use between the antenna and the radio and the antenna height.. Because we can't look at the path loss, there is no way for sure to know what you are trying to talk thru, but for best results you need that antenna at least 40' off the ground.. With 50' of LMR 400 - your loss at @ 440 Mhz would be a loss of about 4 db, and you can't use a PL connector for 70cm, because there is a impedance bump around 300 mhz that throws off the scale of loss. Your best bet is to get a better transmitter that produces more power...
    6 replies | 102 view(s)
  • Sixmeters's Avatar
    Yesterday, 17:03
    I would but my crystal ball is broke, maybe if you could post a couple of pictures of it, would help...
    3 replies | 81 view(s)
  • Sixmeters's Avatar
    Yesterday, 17:01
    The FM Scene in Cypress must be much different than what it is in The USA - because where I live, because most FM 2m repeaters here are cliquish.. Unless they know who you are - and want to talk to you, there is no one to talk to - period! Most of the newer hams are relegated to a handheld radio that doesn't talk anywhere.. To protect their batteries, they only turn them on 5 minutes before a net, they give their ( No Traffic ) and then they quickly turn them back off. Even the older, what should be more knowledgeable hams, doesn't want to be bothered with a 50w mobile, or putting up antennas or operating anything more than ham walkie talkie - like a cell phone... All that is left is the scanner listeners, that sits and listens to their analog police scanners - like they are going to miss something if they don't have it turned on all the time....
    11 replies | 135 view(s)
  • OH8GAD's Avatar
    Yesterday, 15:48
    Brilliant!
    11 replies | 135 view(s)
  • camerart's Avatar
    Yesterday, 15:23
    Hi P, A friend made me a 2mtr Jpole, which is in the loft, that I use for a local net. I m just getting into repeaters,and need a 70cm antenna, I tried the v-2000 in the loft as mentioned. Neither of them are able to do both jobs. What do you suggest please? I am quite happy to mess about with the V-2000. As I said the 70cms gets into the repeater with 0.5W, so I don't mind raising the 2mtr at the expense of the 70cms. Or should I simply start again? C
    6 replies | 102 view(s)
  • paulears's Avatar
    Yesterday, 14:55
    To be honest, on VHF the gain figures are always a bit questionable - they claim just of 3dBd at 2m, with a bit more at 70cm - I suspect you're already at this point. The sections inside are pre-cut so the only thing that the grub screws control is the matching to get a lowish VSWR, I don't think you're going to improve the performance and probably wreck the VSWR. They're reliable compromise antennas, so not brilliant. I have the 2/70cm version and it's selling point is simple that it's a base station for two bands with one feeder.
    6 replies | 102 view(s)
  • camerart's Avatar
    Yesterday, 10:54
    Hi, I have a Diamond V-2000 antenna (70Cms 2Mtr 6Mtr coil on Radial) I can connect to a repeater on 70cms 15 miles away on 0.5W, but it is't good on 2mtrs. Is there a way of tuning the 2mtrs while keeping the 70cms good? I have an antenna analyser for 2mtrs but not 70cms. Here is a photo of the works, showing the coils 2x grub screws and 1x screw. I assume the 1x screw is there hopefully to tune something? Any ideas Camerart.
    6 replies | 102 view(s)
  • 5B4AJB's Avatar
    Yesterday, 04:58
    pretty much everyone?
    11 replies | 135 view(s)
  • 5B4AJB's Avatar
    Yesterday, 04:16
    Nope :p Multi-band antennas are a compromise at best and even single-band antennas are usually resonant at one frequency. Most of the signal a really good VHF/UHF antenna collects is wasted by poor coax. A decent run of Heliax or H100 (or similar) might cost as much as the whole station, but is worth it. Get your discone up as high as possible and feed it with some nice coax, then you'll start pulling in signals...
    2 replies | 98 view(s)
  • 5B4AJB's Avatar
    Yesterday, 04:13
    You can figure out the approximate value by measurement (dimensions). Its been many years since I was at college, but its a function of the total surface area of the plates and the distance between them. Try this calculator. Be aware that they usually have a minimum capacitance too, so, it may have the range of 20-100pF
    3 replies | 81 view(s)
  • FlyGuy's Avatar
    Yesterday, 00:25
    Well, as a private pilot, most of the flying I do is just for fun. I figured I'd take a mobile up, and just see if I can make any contacts. If I don't, so be it. If I do, well then I think that's pretty cool.
    11 replies | 135 view(s)
  • K7KBN's Avatar
    Mon 13th Aug 2018, 22:42
    Connect it to a capacitance meter (and subtract the capacitance of the meter leads).
    3 replies | 81 view(s)
  • DCBUS's Avatar
    Mon 13th Aug 2018, 18:17
    Hello, Can someone please help me identify this variable capacitor. I do not see any brand or model on the unit? It is 9" wide x 7" deep x 6" tall. Thank you
    3 replies | 81 view(s)
  • paulears's Avatar
    Mon 13th Aug 2018, 18:17
    paulears replied to a thread Tuning in Yaesu
    Seems odd to ask a question, get decent answers that clearly have been a bit misunderstood then walk away, with the wrong explanation in your head. The radio never presents a 50 ohm source to the outside world if that antenna is anything other than 50 Ohms - it does it's job by converting one impedance into another, maximising efficiency. one end of an antenna tuner is designed to be 50Ohms, and the other can be whatever is needed.
    14 replies | 456 view(s)
  • Sixmeters's Avatar
    Mon 13th Aug 2018, 16:34
    Who are you going to talk to? I can hear 40+ repeaters at my QTH, and yet not hear much if anything all day long, except the repeater identify from time to time unless there is a net... Would be a perfectly good waste of airplane fuel to fly just for the purpose of wanting to play FM.... Maybe if you tried VHF SSB during a contest you could find people to work, but then you would have to sign aeronautical mobile, and i don't know how it would count for grids and stuff...
    11 replies | 135 view(s)
  • Sixmeters's Avatar
    Mon 13th Aug 2018, 16:31
    Sixmeters replied to a thread Tuning in Yaesu
    Well Obed, not to be combative, but unless you can bend the laws of physics, you cannot make a non resonant antenna resonant by just cancelling out the reactive or resistivity component. As you claimed, all you are doing is tricking the radio to accept what ever is connected to the feed line... As you claimed, all you are doing is changing the impedance of the line at the radio end. Anything not adsorbed by the load or the line is reflected back towards the source, turned into heat. Good for keeping your coffee warm, but not good if you want that power to be used efficiently. How many times have you heard someone brag that they are running 100w.. When in fact what they are radiating is much less than the 100w the transmitter could produce - had the antenna been resonant... Point in case someone misses it is the G5RV. Which is semi resonant on 20 meters, not resonant at all on 10 or 40 meters.. Wanna buy a burned up MFJ antenna tuner, just ask everyone that ever tried tuning their G5RV...
    14 replies | 456 view(s)
  • Obed's Avatar
    Mon 13th Aug 2018, 16:16
    Obed replied to a thread Tuning in Yaesu
    your radio should be able to turn the built in tuner off...
    14 replies | 456 view(s)
  • Obed's Avatar
    Mon 13th Aug 2018, 16:14
    Obed replied to a thread Tuning in Yaesu
    well sixmeters made a technical error in his statement... he said in a perfect world the tuner does not tune the "antenna system" it just tricks the radio... that is not correct... the radio does not know what is out there, it does not know what type or how long the coax, transmission line etc is, it does not know what the antenna is... it only know what it sees at its output... the tuner actually does tune the LOAD to an impedance match...it does not affect the efficiency of the antenna... lots of folks like to use the old wives tale of just "fooling" the radio... it does not do that... it does impedance match the load...lots of radios do have a built in function to reduce the power out if it does not see a good impedance match..l which is the whole load, not just the antenna.
    14 replies | 456 view(s)
  • Obed's Avatar
    Mon 13th Aug 2018, 16:09
    on commercial flights here you can not do it, but private pilots can.
    11 replies | 135 view(s)
  • OH8GAD's Avatar
    Mon 13th Aug 2018, 15:31
    The D220R is for 100 to 1600MHz. Most of the amateur radio bands are fairly close to being harmonically related: 1,8 MHz/160 m, 3,5 MHz/80 m, 7 MHz/40 m, 14 MHz/20 m and 28 MHz/10 m, so you can just string out a length of wire at one of these lengths. It's not perfect, but you should get something. But bear in mind, the HF bands can be rather fickle and event with a perfect antenna for that band, you might not hear anything at all. As well as the long wire, you could knock up a simple antenna tuning unit** from a large variable capacitor and coil of stripped down mains cable and see what you can get. **Yes, yes, I know some folk consider these to be instruments of the devil, but hey, you're just starting out and it's a good place to start*learning how adding things work.
    2 replies | 98 view(s)
  • OH8GAD's Avatar
    Mon 13th Aug 2018, 15:15
    It's country by country: In the UK, it is forbidden, but in Finland, you must have permission from the Finnish Transport Safety Agency (TraFi) and the pilot of the aircraft.
    11 replies | 135 view(s)
  • Gopher5's Avatar
    Mon 13th Aug 2018, 14:31
    Gopher5 replied to a thread Mobile Radios IC706MK11G Won't Key in CW Mode in Icom
    Tnx very much Eric. That was the problem. Q4-CW PADDLE was set at default or (n). I changed it to (off) and it will now key. I think I am getting too old with these new technology radios as it was simple to operate in the old Collins KWM2A and 30L1 era. 73's es tnx agn, Forrest K0MK
    3 replies | 98 view(s)
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