At 06:29 AM 05/08/06, you wrote: >Re: Crossband/Portable repeaters > >- Here in Colorado, we have two 2 Meter pairs designated for statewide >use for portable/emergency/special event repeaters. These pairs get used to >fill in the dead spots when emergencies occur. A number of clubs and ARES >groups have portable repeaters set up on these pairs. (Good band planning >by whoever put these in place years ago.)
Yeah, good coordinators rarely get the thanks they deserve. Our portable repeater pair is 144.93 / 147.595 >- Some of the emcomm folks use dualband transceivers with crossband >repeat as a inexpensive way to extend radio range (often used to extend >HT range from inside a building or other bad spot). > These radios don't meet the letter of the law (FCC regs) with regard >to identification (my opinion, you mileage may vary.) I have one set up in my vehicle to help me get into our UHF system from inside a building. It uses a 420.something input and a 443.something output. I have a extra memory position set up on the handheld that listens to the system output and talks on the 420 channel. We are coordinated on that 420 channel as a link frequency and the receiver that hears that frequency is over 100 miles away and is on a directional antenna pointed at the mountaintop that the repeater is on, so it's not going to hear my HT inside a building. I'm the only one who is going to use that mobile extender and I am sure to ID it with "through the WA6ILQ mobile repeater" as needed. However Kevin has banned rules and regs discussions on this list for good reason - they generate a lot of heat and fire and discontent and nothing gets resolved - and this is getting close to that area so I'm going to drop the regs topic with this posting. Any regs followups to personal mail, or technical followups to the list. > - We do not have any designated frequencies for crossbanding to 440 MHz >in the bandplan. Most people just find some lightly used uhf >simplex frequency. I've been known to use a repeater input frequency from some out-of-the-area system (with permission from the system owner) and use a different PL tone on top of that. For a long time I had a roll-around Pelican case (think of a Samsonite rollaround suitcase that's the width of a rack panel and a foot thick) with a 25w Micor mobile (switchable between the two local test pairs) with a duplexer, a Scom 7K and a Optima sealed battery in it. Roll it into a convention hotel room, stand it in a corner opened up for ventilation, hook up an antenna to the duplexer (a 6" mag mount stuck to the bottom of a metal trash can lid and hanging upside down from a top floor room balcony gets out a lot better than you would think). > - If conventional transceivers are used, the power needs to be reduced >or additional cooling supplied due to 100% duty cycle operation. A forgotten fact is that 25w Micor mobiles are continuous duty. > - I constructed a crossband repeater using two transceivers and an >NHRC-6 controller that knows > how to handle the ID of two transmitters appropriately (most >repeater controllers do not). > http://www.nhrc.net/nhrc-6 A good tip - I'd forgotten that. BTW the -7 will also. >- One issue with a vhf/uhf crossband repeat set up working into a >repeater....the repeater transmitter > must drop before the crossband repeater can turn the link around. >Shortening the hang time on > the conventional repeater (or using CTCSS that drops with the >received signal) helps this issue. We ran into that problem in one of the 1980s Rose Parades... I forget which year... the floats are built at over 15 locations and have to convoy in (some from 40 miles away) and arrive at the formation area in the proper sequence. Formation is on a city street and one float passing another is difficult - ever try and parallel park a 5-ton float that's 50 feet long and has a 300-degree blind spot? My assignment was at one of the float construction areas and could not get into the main parade control 147.27 repeater from there... I had a 440-to-2m crossband repeater in my car (at that time it was two HT-200s) and the guys at Parade Control had to wait for the system to completely drop out before I could answer a call. A while later another ham showed up with a 10w mobile and a gellcell in a backpack complete with an 18" spike antenna on a microphone gooseneck strapped to one of the shoulder straps. A few years later an outbound CTCSS encoder slaved to inbound COR was added to the repeater to support the crossbanders.... I wish that more repeater owners would add that. >73, >Bob K0NR >[EMAIL PROTECTED] Mike WA6ILQ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
