Re: [digitalradio] Re: Domnio, PAX etc
Is it the band or the mode ? ? ? It seems to me in my 35 years as a ham that 80 and 160 are at it's best this time of year. John, W0JAB At 09:51 PM 2/13/2007, you wrote: Hi Bill, Yes, busy night tonight on 160:) The question I wanted to ask the group was whether they have found on the lower bands (especially 80 and 160) that DominoEX (DEX) is better when operating at a given speed such as DEX11/without FEC or is it better at twice the speed, but with FEC, e.g., DEX 22 with FEC?
Re: [digitalradio] Re: Domnio, PAX etc
domino EX , on multipsk. sorry if I mis-lead you Ozhan John - Original Message - From: ozhan onder To: digitalradio@yahoogroups.com Sent: Wednesday, February 14, 2007 12:15 AM Subject: [digitalradio] Re: Domnio, PAX etc Hello John, What is DEX John?,a new digi mode to play with?..Tell us a little bit.. vy tnx. 73's de Özhan TA3BQ --- In digitalradio@yahoogroups.com, John Bradley [EMAIL PROTECTED] wrote: With respect to MT63 , I have used it extensively in the past and found it wanting, especially trying to tune a weak signal under less than optimum conditions, as the noise covered the audio up. Under side by side tests it did not copy as well as Olivia (1000/32) . probably half as well on the day tested between 2 stations 1500 miles apart on 20M . that day likely a 2 hop. MFSK is fussy to tune, and with some folks using older rigs, is subject to drift during a long TX at power. Does get through, however, as well as OLIVIA 500/16 , and much better than PSK31, again trying multiple modes between distant stations. DEX? I always seem to be in the wrong place at the wrong time, so have only used DEX locally. Look forward to playing with DEX over a distance Will sit on 14073 center freq in the AM and please let me know if you are playing on 80 or 160 . Monday night had some good luck with OLIVIA 500/16 over a considerable distance on 160m tnx John VE5MU -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.441 / Virus Database: 268.17.39/686 - Release Date: 2/14/2007 7:54 AM
[digitalradio] Re: Domnio, PAX etc
--- In digitalradio@yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Rick, I hope you or someone is making a list of which modes work the best on each band and in varying conditions This harks back to my recent comment on Olivia - how one night I was getting solid copy on one station and no copy at all on another, when the two were in QSO and I could hear both of them equally loud. It's going to be hard to get sure-fire evaluation because we don't quite know all the conditions. So I would expect to see that A is better than B under certain conditions, but at another time B is better than A under apprently the same conditions. This is where the channel simulator software can help, since with it you at least know what the conditions are.
RE: [digitalradio] Re: Domnio, PAX etc
STOMP STOMP STOPM...for the 10th time...use Moe Wheatley's PathSim. It may not be the best in the world but is does have some variables and Moe has made it freely available. Check out a mode with it under all the variables that his simulator will allow and then chack you on-the-air reports against the standard. We (amateur radio operators) CAN so some serious scientific study of new digital modes and help the entire amateur radio communinity...but we MUST work in concert. Walt/K5YFW Sorry, not picking on you Rick...just us. -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of jhaynesatalumni Sent: Wednesday, February 14, 2007 10:50 AM To: digitalradio@yahoogroups.com Subject: [digitalradio] Re: Domnio, PAX etc --- In digitalradio@yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Rick, I hope you or someone is making a list of which modes work the best on each band and in varying conditions This harks back to my recent comment on Olivia - how one night I was getting solid copy on one station and no copy at all on another, when the two were in QSO and I could hear both of them equally loud. It's going to be hard to get sure-fire evaluation because we don't quite know all the conditions. So I would expect to see that A is better than B under certain conditions, but at another time B is better than A under apprently the same conditions. This is where the channel simulator software can help, since with it you at least know what the conditions are. Announce your digital presence via our DX Cluster telnet://cluster.dynalias.org Our other groups: http://groups.yahoo.com/group/dxlist/ http://groups.yahoo.com/group/themixwgroup http://groups.yahoo.com/group/contesting http://groups.yahoo.com/group/wnyar http://groups.yahoo.com/group/Omnibus97 Yahoo! Groups Links
Re: [digitalradio] Re: Domnio, PAX etc
I have not used Moe's simulator yet. It takes my second PC that is not working now. Could you tell people like me which are those variables available on Moe's simulator besides gaussian noise ? So far I have only seen reports on gaussian noise using Moe's simulator. And agreed. Working in concert is a MUST. Flaming each other is the least we need. Jose, CO2JA DuBose Walt Civ AETC CONS/LGCA wrote: STOMP STOMP STOPM...for the 10th time...use Moe Wheatley's PathSim. It may not be the best in the world but is does have some variables and Moe has made it freely available. Check out a mode with it under all the variables that his simulator will allow and then chack you on-the-air reports against the standard. We (amateur radio operators) CAN so some serious scientific study of new digital modes and help the entire amateur radio communinity...but we MUST work in concert. Walt/K5YFW Sorry, not picking on you Rick...just us. __ V Conferencia Internacional de Energía Renovable, Ahorro de Energía y Educación Energética. 22 al 25 de mayo de 2007 Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.cujae.edu.cu/eventos/cier
Re: [digitalradio] Re: Domnio, PAX etc
I am afraid that you can only reach a determination on SOME of the data gathered with ionospheric data archives. I think that Walt's proposal is a very good idea, but only part of it will have verifiable path conditions. Nevertheless, you have to walk the tunnel to get to see the light at the end... A deterministic study will be more complex than building the database, which is not a trivial effort, even taking into acount that some noise will creep into it. With the database, as I see it NOW, you will be able to derive statistically which mode works the best most of the time, but not WHY. It is indeed very complex to achieve a deterministic explanation, but if research on it it is not started you'll never know WHY. A simulator study will fall short, because you have to know how to weight the variables, the amount of white noise, the amount of thunder crashes and thrashed blocks, the amount of ionospheric doppler, the amount of delay spread, etc. Even the amount of QRM on a given moments has a weight. A gaussian noise behavior study will only tell a part of the story. It is better than nothing, but it certainly falls short. With the available modes, each one has strenghts and weaknesses, which are different among the different modulations and FEC/ARQ strategies. On the other hand, a simulator that can provide the beforementioned effects could be used to derive tables of performance, which might be quite prectical. You would have then to sort out which are the more prevalent variables on a given situation. I am very interested on this experiment. Jose, CO2JA jhaynesatalumni wrote: --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Rick, I hope you or someone is making a list of which modes work the best on each band and in varying conditions This harks back to my recent comment on Olivia - how one night I was getting solid copy on one station and no copy at all on another, when the two were in QSO and I could hear both of them equally loud. It's going to be hard to get sure-fire evaluation because we don't quite know all the conditions. So I would expect to see that A is better than B under certain conditions, but at another time B is better than A under apprently the same conditions. This is where the channel simulator software can help, since with it you at least know what the conditions are. __ V Conferencia Internacional de Energía Renovable, Ahorro de Energía y Educación Energética. 22 al 25 de mayo de 2007 Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.cujae.edu.cu/eventos/cier
RE: [digitalradio] Re: Domnio, PAX etc
You can establsih a base line for each mode with a simulator. And while the propagation conditions vary a great deal, if you gather enough data, then you begin to get an average or norm. This is much like keeping medical records on diseases treated with a specific drug...while no one case is alike, after a while you can see a norm on what each medicine can do. Or in another way, we can keep tabs on the life span of Cuban Cigar smokers vs. those who smoke inferior cigars and see who lives the longest. But you may need to keep track of 10,000 smokers. In out case, perhaps we can get several thousand QSOs for each mode on each band. Walt/K5YFW -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of Jose A. Amador Sent: Wednesday, February 14, 2007 1:47 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: Domnio, PAX etc I am afraid that you can only reach a determination on SOME of the data gathered with ionospheric data archives. I think that Walt's proposal is a very good idea, but only part of it will have verifiable path conditions. Nevertheless, you have to walk the tunnel to get to see the light at the end... A deterministic study will be more complex than building the database, which is not a trivial effort, even taking into acount that some noise will creep into it. With the database, as I see it NOW, you will be able to derive statistically which mode works the best most of the time, but not WHY. It is indeed very complex to achieve a deterministic explanation, but if research on it it is not started you'll never know WHY. A simulator study will fall short, because you have to know how to weight the variables, the amount of white noise, the amount of thunder crashes and thrashed blocks, the amount of ionospheric doppler, the amount of delay spread, etc. Even the amount of QRM on a given moments has a weight. A gaussian noise behavior study will only tell a part of the story. It is better than nothing, but it certainly falls short. With the available modes, each one has strenghts and weaknesses, which are different among the different modulations and FEC/ARQ strategies. On the other hand, a simulator that can provide the beforementioned effects could be used to derive tables of performance, which might be quite prectical. You would have then to sort out which are the more prevalent variables on a given situation. I am very interested on this experiment. Jose, CO2JA jhaynesatalumni wrote: --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Rick, I hope you or someone is making a list of which modes work the best on each band and in varying conditions This harks back to my recent comment on Olivia - how one night I was getting solid copy on one station and no copy at all on another, when the two were in QSO and I could hear both of them equally loud. It's going to be hard to get sure-fire evaluation because we don't quite know all the conditions. So I would expect to see that A is better than B under certain conditions, but at another time B is better than A under apprently the same conditions. This is where the channel simulator software can help, since with it you at least know what the conditions are. __ V Conferencia Internacional de Energía Renovable, Ahorro de Energía y Educación Energética. 22 al 25 de mayo de 2007 Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.cujae.edu.cu/eventos/cier Announce your digital presence via our DX Cluster telnet://cluster.dynalias.org Our other groups: http://groups.yahoo.com/group/dxlist/ http://groups.yahoo.com/group/themixwgroup http://groups.yahoo.com/group/contesting http://groups.yahoo.com/group/wnyar http://groups.yahoo.com/group/Omnibus97 Yahoo! Groups Links
RE: [digitalradio] Re: Domnio, PAX etc
Hummm, let me dig up the book or go back online and download it. We can work in concert and try not to tell fish stories about our QSOs. Hi Hi. Walt -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of Jose A. Amador Sent: Wednesday, February 14, 2007 1:58 PM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: Domnio, PAX etc I have not used Moe's simulator yet. It takes my second PC that is not working now. Could you tell people like me which are those variables available on Moe's simulator besides gaussian noise ? So far I have only seen reports on gaussian noise using Moe's simulator. And agreed. Working in concert is a MUST. Flaming each other is the least we need. Jose, CO2JA DuBose Walt Civ AETC CONS/LGCA wrote: STOMP STOMP STOPM...for the 10th time...use Moe Wheatley's PathSim. It may not be the best in the world but is does have some variables and Moe has made it freely available. Check out a mode with it under all the variables that his simulator will allow and then chack you on-the-air reports against the standard. We (amateur radio operators) CAN so some serious scientific study of new digital modes and help the entire amateur radio communinity...but we MUST work in concert. Walt/K5YFW Sorry, not picking on you Rick...just us. __ V Conferencia Internacional de Energía Renovable, Ahorro de Energía y Educación Energética. 22 al 25 de mayo de 2007 Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.cujae.edu.cu/eventos/cier Announce your digital presence via our DX Cluster telnet://cluster.dynalias.org Our other groups: http://groups.yahoo.com/group/dxlist/ http://groups.yahoo.com/group/themixwgroup http://groups.yahoo.com/group/contesting http://groups.yahoo.com/group/wnyar http://groups.yahoo.com/group/Omnibus97 Yahoo! Groups Links
Re: [digitalradio] Re: Domnio, PAX etc
Hello to all, There are also some basic axioms (I suppose so) as: 1) Doppler iosnospheric modulation acts on PSK modes (the phase is dancing randomly, the Costas loop cannot stabilize and the PSK decoding is quite impossible). The more the modulation speed is, the less this Doppler acts on the phase difference (which determines the bit). Hence, PSK10 is very sensitive to Doppler, PSK31 is less sensitive and the effect is very weak on PSK125. 2) Doppler ionospheric modulation effect is linear with the HF frequency (smaller in 3.5 MHz that in 7 MHz). It seems logical but I'm not so sure of it... 73 Patrick - Original Message - From: Jose A. Amador To: digitalradio@yahoogroups.com Sent: Wednesday, February 14, 2007 8:46 PM Subject: Re: [digitalradio] Re: Domnio, PAX etc I am afraid that you can only reach a determination on SOME of the data gathered with ionospheric data archives. I think that Walt's proposal is a very good idea, but only part of it will have verifiable path conditions. Nevertheless, you have to walk the tunnel to get to see the light at the end... A deterministic study will be more complex than building the database, which is not a trivial effort, even taking into acount that some noise will creep into it. With the database, as I see it NOW, you will be able to derive statistically which mode works the best most of the time, but not WHY. It is indeed very complex to achieve a deterministic explanation, but if research on it it is not started you'll never know WHY. A simulator study will fall short, because you have to know how to weight the variables, the amount of white noise, the amount of thunder crashes and thrashed blocks, the amount of ionospheric doppler, the amount of delay spread, etc. Even the amount of QRM on a given moments has a weight. A gaussian noise behavior study will only tell a part of the story. It is better than nothing, but it certainly falls short. With the available modes, each one has strenghts and weaknesses, which are different among the different modulations and FEC/ARQ strategies. On the other hand, a simulator that can provide the beforementioned effects could be used to derive tables of performance, which might be quite prectical. You would have then to sort out which are the more prevalent variables on a given situation. I am very interested on this experiment. Jose, CO2JA jhaynesatalumni wrote: --- In digitalradio@yahoogroups.com mailto:digitalradio%40yahoogroups.com, DuBose Walt Civ AETC CONS/LGCA [EMAIL PROTECTED] wrote: Rick, I hope you or someone is making a list of which modes work the best on each band and in varying conditions This harks back to my recent comment on Olivia - how one night I was getting solid copy on one station and no copy at all on another, when the two were in QSO and I could hear both of them equally loud. It's going to be hard to get sure-fire evaluation because we don't quite know all the conditions. So I would expect to see that A is better than B under certain conditions, but at another time B is better than A under apprently the same conditions. This is where the channel simulator software can help, since with it you at least know what the conditions are. __ V Conferencia Internacional de Energía Renovable, Ahorro de Energía y Educación Energética. 22 al 25 de mayo de 2007 Palacio de las Convenciones, Ciudad de la Habana, Cuba http://www.cujae.edu.cu/eventos/cier
Re: [digitalradio] Re: Domnio, PAX etc
My experience indicates that Olivia 16-500 and MFSK are very solid modes for the conditions that we presently are experiencing during the current phase of the sunspot cycle. I, like Bill, am amazed at Olivia's ability to copy signals that you can barely see on the waterfal and not even hear via audio. 30 meter propagation is sometimes not very good and Olivia really shines on this band. I have had a dozen or so QSOs with MT63 and that mode seems to give a binary result. There is a lot of FEC going on in this mode so it should work very well under poor conditions. If you can copy, the copy is excellent -- near 100%; otherwise, no copy whatsover. Not too many people seem to use this mode so I believe I need more experience before having a good appreciation of this mode under various conditions. 73, Bernie - Original Message - From: Bill McLaughlin To: digitalradio@yahoogroups.com Sent: Tuesday, February 13, 2007 11:44 PM Subject: [digitalradio] Re: Domnio, PAX etc Well can only relate my impressions; hope others chime in I think even though DominoEX halves the speed when FEC in engaged, it is well worth the speed trade-off. 160/80 seems to vary night to night in this regard; probably due to qrn and multipath. It also depends on one's ability/willingness to read between the lines as there are a few hits at the higher speeds and one needs to brain- error correct as there is no ARQ. As for Throb; I find it very sensitive, but at times it does not seem to decode signals that are audiblenever figured out why. As for MFSK modes, yes they are very frequency sensitive although I have had little trouble tuning most, aside from a few that took a long time to sync. Multipsk's AFC seems to lock quite well on MFSK signals, not sure how other software doescertainly DominoEX is superior in that sense. I have not worked enought MT63 to comment. I have had better luck with CHIP64 although both seem to not be qrp modes and require a high signal to noise ratio... It is odd (but probably not so if studied correctly), on some nights (condx) certain modes just seem to work better under various conditionsat times I am amazed that Olivia can decode signals in the mudother times I swear at it...one night on a VHF path only PSKAM10 or JT65B would get through; guess that what makes it all fun. 73 Bill N9DSJ --- In digitalradio@yahoogroups.com, KV9U [EMAIL PROTECTED] wrote: Hi Bill, Yes, busy night tonight on 160:) The question I wanted to ask the group was whether they have found on the lower bands (especially 80 and 160) that DominoEX (DEX) is better when operating at a given speed such as DEX11/without FEC or is it better at twice the speed, but with FEC, e.g., DEX 22 with FEC? Tentatively, I almost want to say that it may be better at the higher speed with FEC. If true, and I am not sure it is, it could be because the higher speed still has a fairly low baud rate, even for some serious multipath on the lower bands. The 77 wpm speed with DEX22/FEC is faster than is comfortable for keyboarding so a slower speed is not bad. The DEX11/FEC does seem quite robust, even with static crashes and who knows how much multipath. Of course you can never get 100% copy under certain conditions when too much of the data is damaged and the Viterbi decoder can not reconstruct the character. Then an ARQ mode would be needed. I wonder how well this type of mode would work with a PSKmail type of program? I know that I had a very difficult time reading a PSK31 signal that was up the band from me. The earlier station that I was talking with for our weekly sked for experimenting with these modes at a short distance of about 35 miles or so indicated that he had good luck with MT-63 in the past but the faster (wider) mode seemed to work better due to having the data spread out so far. Has anyone else found this on the lower bands with MT-63? The ability to only approximately tune in DEX signals is extremely helpful for me as I find that I have a difficult time locking in on MFSK16. Earlier tonight WA9HCZ and I started our experiments with ThrobX and although he could copy me solid, I could never decode his signal. So I must have been doing something wrong. Ideally, these modes that need extremely accurate tuning, should have some kind of display to help you determine if you are far from locking in to the signal or not. Something like we had with the early PSK programs. 73, Rick, KV9U
[digitalradio] Re: Domnio, PAX etc
Hi Rick, Just FYI; you and Dave (K3GAU) were solid copy on DoiminoEX on 160 tonight despite me using my 80 meter antenna. Actually seemed best using 22 baud with FEC...one or two static crash hits, but overall impressive considering my antenna limitations on 160 meters. 73 Bill N9DSJ --- In digitalradio@yahoogroups.com, KV9U [EMAIL PROTECTED] wrote: W1OER was on 14.073 just now so worked him and chatted a bit. He was calling in DEX11/FEC and I was set up for DEX11 w/o FEC. And then realized that I was actually on FEC because I had the RS ID Detect turned on. 73, Rick, KV9U
[digitalradio] Re: Domnio, PAX etc
Well can only relate my impressions; hope others chime in I think even though DominoEX halves the speed when FEC in engaged, it is well worth the speed trade-off. 160/80 seems to vary night to night in this regard; probably due to qrn and multipath. It also depends on one's ability/willingness to read between the lines as there are a few hits at the higher speeds and one needs to brain- error correct as there is no ARQ. As for Throb; I find it very sensitive, but at times it does not seem to decode signals that are audiblenever figured out why. As for MFSK modes, yes they are very frequency sensitive although I have had little trouble tuning most, aside from a few that took a long time to sync. Multipsk's AFC seems to lock quite well on MFSK signals, not sure how other software doescertainly DominoEX is superior in that sense. I have not worked enought MT63 to comment. I have had better luck with CHIP64 although both seem to not be qrp modes and require a high signal to noise ratio... It is odd (but probably not so if studied correctly), on some nights (condx) certain modes just seem to work better under various conditionsat times I am amazed that Olivia can decode signals in the mudother times I swear at it...one night on a VHF path only PSKAM10 or JT65B would get through; guess that what makes it all fun. 73 Bill N9DSJ --- In digitalradio@yahoogroups.com, KV9U [EMAIL PROTECTED] wrote: Hi Bill, Yes, busy night tonight on 160:) The question I wanted to ask the group was whether they have found on the lower bands (especially 80 and 160) that DominoEX (DEX) is better when operating at a given speed such as DEX11/without FEC or is it better at twice the speed, but with FEC, e.g., DEX 22 with FEC? Tentatively, I almost want to say that it may be better at the higher speed with FEC. If true, and I am not sure it is, it could be because the higher speed still has a fairly low baud rate, even for some serious multipath on the lower bands. The 77 wpm speed with DEX22/FEC is faster than is comfortable for keyboarding so a slower speed is not bad. The DEX11/FEC does seem quite robust, even with static crashes and who knows how much multipath. Of course you can never get 100% copy under certain conditions when too much of the data is damaged and the Viterbi decoder can not reconstruct the character. Then an ARQ mode would be needed. I wonder how well this type of mode would work with a PSKmail type of program? I know that I had a very difficult time reading a PSK31 signal that was up the band from me. The earlier station that I was talking with for our weekly sked for experimenting with these modes at a short distance of about 35 miles or so indicated that he had good luck with MT-63 in the past but the faster (wider) mode seemed to work better due to having the data spread out so far. Has anyone else found this on the lower bands with MT-63? The ability to only approximately tune in DEX signals is extremely helpful for me as I find that I have a difficult time locking in on MFSK16. Earlier tonight WA9HCZ and I started our experiments with ThrobX and although he could copy me solid, I could never decode his signal. So I must have been doing something wrong. Ideally, these modes that need extremely accurate tuning, should have some kind of display to help you determine if you are far from locking in to the signal or not. Something like we had with the early PSK programs. 73, Rick, KV9U
Re: [digitalradio] Re: Domnio, PAX etc
With respect to MT63 , I have used it extensively in the past and found it wanting, especially trying to tune a weak signal under less than optimum conditions, as the noise covered the audio up. Under side by side tests it did not copy as well as Olivia (1000/32) . probably half as well on the day tested between 2 stations 1500 miles apart on 20M . that day likely a 2 hop. MFSK is fussy to tune, and with some folks using older rigs, is subject to drift during a long TX at power. Does get through, however, as well as OLIVIA 500/16 , and much better than PSK31, again trying multiple modes between distant stations. DEX? I always seem to be in the wrong place at the wrong time, so have only used DEX locally. Look forward to playing with DEX over a distance Will sit on 14073 center freq in the AM and please let me know if you are playing on 80 or 160 . Monday night had some good luck with OLIVIA 500/16 over a considerable distance on 160m tnx John VE5MU
[digitalradio] Re: Domnio, PAX etc
Hello John, What is DEX John?,a new digi mode to play with?..Tell us a little bit.. vy tnx. 73's de Özhan TA3BQ --- In digitalradio@yahoogroups.com, John Bradley [EMAIL PROTECTED] wrote: With respect to MT63 , I have used it extensively in the past and found it wanting, especially trying to tune a weak signal under less than optimum conditions, as the noise covered the audio up. Under side by side tests it did not copy as well as Olivia (1000/32) . probably half as well on the day tested between 2 stations 1500 miles apart on 20M . that day likely a 2 hop. MFSK is fussy to tune, and with some folks using older rigs, is subject to drift during a long TX at power. Does get through, however, as well as OLIVIA 500/16 , and much better than PSK31, again trying multiple modes between distant stations. DEX? I always seem to be in the wrong place at the wrong time, so have only used DEX locally. Look forward to playing with DEX over a distance Will sit on 14073 center freq in the AM and please let me know if you are playing on 80 or 160 . Monday night had some good luck with OLIVIA 500/16 over a considerable distance on 160m tnx John VE5MU
