Re: [Repeater-Builder] Re: 23cm antenna for DSTAR
At 16:21 7/29/2008, johnmichaelwelton wrote: >Omni directional, this will be on top of the one of the tallest >building in Charleston (not saying much :-). Feedline run will be >about 75 feet.John/N4SJW I recommend the Hustler Spirit line of 1.2Gig antennas. Tim Barrett K6BIV K6MDD Mt. Diablo D-Star Trustee 925 427-5197 I have hit this antenna full strength from an ID-1 on voice, but the data bandwidth is so great that data transmission failed from 32 miles away, using a Comet 16-el yagi on my end with an LMR-400 feedline. -- Dave Gomberg, San Francisco NE5EE gomberg1 at wcf dot com All addresses, phones, etc. at http://www.wcf.com/ham/info.html -
Re: [Repeater-Builder] Re: 23cm antenna for DSTAR
At 16:21 7/29/2008, johnmichaelwelton wrote: >Omni directional, this will be on top of the one of the tallest >building in Charleston (not saying much :-). Feedline run will be >about 75 feet.John/N4SJW I recommend the Hustler Spirit line of 1.2Gig antennas. Tim Barrett K6BIV K6MDD Mt. Diablo D-Star Trustee 925 427-5197 I have hit this antenna full strength from an ID-1 on voice, but the data bandwidth is so great that data transmission failed from 32 miles away, using a Comet 16-el yagi on my end with an LMR-400 feedline. -- Dave Gomberg, San Francisco NE5EE gomberg1 at wcf dot com All addresses, phones, etc. at http://www.wcf.com/ham/info.html -
[Repeater-Builder] Re: 23cm antenna for DSTAR
There isn't going to be much warning before that RF output module self-destructs. When he has to foot the bill for a new RF module (or even transistors), even if he replaces it/them himself, I'll bet that power set pot will be glued in place at 10 watts. Just hope he isn't too long-winded. Tom --- In Repeater-Builder@yahoogroups.com, Nate Duehr <[EMAIL PROTECTED]> wrote: > > johnmichaelwelton wrote: > > Any recommendations for a 1.2GHz antenna to be used in a DSTAR DD/DV > > application at a commercial site (hospital)? > > > > John/N4SJW > > Charleston, SC > > For a repeater or base station (ID-1)? > > The options are somewhat limited out there. Sadly it seems the > Comet/Diamond type antennas are some that a lot of people are using, and > commercial quality options are few. > > For our repeater, which is on a mountain on the West side of the city, > we used a custom-built 120 degree panel reflector. > > Sending the extra RF of an omnidirectional antenna back into the > mountains, turned out to be a problem for our analog 1.2 machine years > ago, so we avoided it and went straight to something with some gain > toward town on the D-STAR system. > > DV (voice) on D-STAR 1.2 acts similar to any other analog 1.2 GHz > repeater. DD (high speed data) being 100 KHz wide, requires more gain > to go the same distance. > > Gain antennas are often necessary for good links on DD... a 10W radio, > 100 KHz wide, isn't much signal left to work with a the far end. > > There is at least one ham running around saying he's bumped his ID-1 to > 20W with no ill effects by finding the power setting pot inside and > cranking it wide open. Not sure I'd do that, but just relaying the > info. I'd want to look at it on a spectrum analyzer and also keep a > very close eye on it for heat load if I were going to mess with the > power setting in the rig. But his reports are that his ID-1 is > surviving the abuse, just fine so far. > > > Nate WY0X >
[Repeater-Builder] Re: 23cm antenna for DSTAR
--- In Repeater-Builder@yahoogroups.com, "johnmichaelwelton" <[EMAIL PROTECTED]> wrote: > > Any recommendations for a 1.2GHz antenna to be used in a DSTAR DD/DV > application at a commercial site (hospital)? > > John/N4SJW > Charleston, SC > I do not have a DStar repeater but just analog voice and have had a Comet GP-21 up on the top of a 275' tower since june 02. Its been a solid performer for me. I would not recommend a multiband omni as they are usually multi section antennas and that leads to more going wrong with it over time. The base of the tower is at about 100' above sea level. My coverage with the GP-21 is about 25 miles out for the 10watt mobiles over mostly flat terrain. Portables at 1 watt out to about 10 to 15 miles if you pick your spot well. See info below .dan n2aym http://www.rigpix.com/antennas/comet_gp21.htm GP-21 Specs Mono Band 1240-1300MHz Base/Repeater Antenna Gain & Wave: 14.9dBi 1⁄2 wave x 21 VSWR: 1.5:1 or less Max Power: 100 watts Length: 8' Weight: 2 lbs. 8 ozs. Mounting Mast Diameter: 11⁄4-21⁄2" Connector: N-Type Construction: Single-piece fiberglass
Re: [Repeater-Builder] Re: 23cm antenna for DSTAR
johnmichaelwelton wrote: > Nate, what type of coverage are you getting in the Denver area for > 1.2 data and voice? How well does the building penetration compare to > 440MHz FM voice rptrs up on the mountain? > > John/N4SJW Crappy right now. ;-) The temporary site near Boulder, CO has a ridge-line between Boulder and Denver. It can just barely "see" over it, but it's not doing so hot. Well, at least not down where I live. Another problem is we're all so spread out... I'm a LONG way from the repeater site and don't really have a clear line-of-sight shot for 1.2 GHz. Just about everywhere in the city will be line-of-sight once we get it up to the high site. So, I've put off all the DD testing (unless I feel like going mobile in my relatively small Jeep with a laptop and a borrowed ID-1 that I really don't want to damage or even scratch up in any way)... for the moment. An opposite-polarized 34-element yagi (yeah yeah, I know... it's also borrowed and I didn't want to do major surgery on it to change it's mounting brackets, since the boom is thin -- end up drilling holes and that boom's gonna break someday after I give it back to the VHF+ contesters that own it!) is barely able to get into the system in DV mode from my QTH 35 miles away. I don't always hold the repeater open. DD just isn't gonna happen... So when we get it up higher, we'll see how it does up there. I am hearing rumblings of "2 weeks" for that... but I'm not in charge of the move, and there's a crew hard at work changing other things on UHF up there to make the site capable of having the UHF D-STAR module there. (There were some UHF links real close to the repeater frequencies now used for digital/narrowband on UHF in Colorado, and the group using them is graciously changing their linking frequencies so the UHF D-STAR repeater will work up there at the same site. That's what's been going on up there and why we're not up there yet... they had a number of sites to change, not just the "hub".) Nate WY0X
[Repeater-Builder] Re: 23cm antenna for DSTAR
Nate, what type of coverage are you getting in the Denver area for 1.2 data and voice? How well does the building penetration compare to 440MHz FM voice rptrs up on the mountain? John/N4SJW --- In Repeater-Builder@yahoogroups.com, Nate Duehr <[EMAIL PROTECTED]> wrote: > > johnmichaelwelton wrote: > > Any recommendations for a 1.2GHz antenna to be used in a DSTAR DD/DV > > application at a commercial site (hospital)? > > > > John/N4SJW > > Charleston, SC > > For a repeater or base station (ID-1)? > > The options are somewhat limited out there. Sadly it seems the > Comet/Diamond type antennas are some that a lot of people are using, and > commercial quality options are few. > > For our repeater, which is on a mountain on the West side of the city, > we used a custom-built 120 degree panel reflector. > > Sending the extra RF of an omnidirectional antenna back into the > mountains, turned out to be a problem for our analog 1.2 machine years > ago, so we avoided it and went straight to something with some gain > toward town on the D-STAR system. > > DV (voice) on D-STAR 1.2 acts similar to any other analog 1.2 GHz > repeater. DD (high speed data) being 100 KHz wide, requires more gain > to go the same distance. > > Gain antennas are often necessary for good links on DD... a 10W radio, > 100 KHz wide, isn't much signal left to work with a the far end. > > There is at least one ham running around saying he's bumped his ID- 1 to > 20W with no ill effects by finding the power setting pot inside and > cranking it wide open. Not sure I'd do that, but just relaying the > info. I'd want to look at it on a spectrum analyzer and also keep a > very close eye on it for heat load if I were going to mess with the > power setting in the rig. But his reports are that his ID-1 is > surviving the abuse, just fine so far. > > > Nate WY0X >
[Repeater-Builder] Re: 23cm antenna for DSTAR
Omni directional, this will be on top of the one of the tallest building in Charleston (not saying much :-). Feedline run will be about 75 feet. John/N4SJW --- In Repeater-Builder@yahoogroups.com, Dave Gomberg <[EMAIL PROTECTED]> wrote: > > At 10:01 7/29/2008, johnmichaelwelton wrote: > >Any recommendations for a 1.2GHz antenna to be used in a DSTAR DD/DV > >application at a commercial site (hospital)? > > > >John/N4SJW > >Charleston, SC > > Do you want directional or omnidirectional??? > > > > > > > > > > > > > > > >Yahoo! Groups Links > > > > > > > > > >No virus found in this incoming message. > >Checked by AVG - http://www.avg.com > >Version: 8.0.138 / Virus Database: 270.5.7/1580 - Release Date: > >7/29/2008 5:26 PM > > > -- > Dave Gomberg, San Francisco NE5EE gomberg1 at wcf dot com > All addresses, phones, etc. at http://www.wcf.com/ham/info.html > - >
