[Repeater-Builder] Mobile Duplexer Question
Iacquireda Phelps Dodge 636 3/3 mobile duplexer tuned for TX freq. of 163.8xxx and a RX freq. of 167.5xxx. What I was wondering was if this could be tuned down into the ham band with any success for a mobile repeater using some hand held radios. I was looking in my Tessco catalog and saw that this unit resembles the RFS Celwave 636-6A-3/3 with specifications of: Freq. range 164-174 Mhz, max power 50 watts, min. separation 4.5 Mhz, insertion loss 1.2 db, isolation 80 db both TX and RX. I then looked at the the RFS Celwave 636-6A-1/3, which is exactly the same aappearanceand specs. except for the freq. range, which is 144-154 Mhz.That made me question, are these duplexers the same onlytuned from the factory differently giving it the slightly different model number. Or are they completely different inside and not worth the trouble of retuning. The tuning rod are sticking out a good ways, about an inch. So maybe there is some room for adjustment. If anyone has messed around with a ssimilarunit or has any info on this unit and could share their stories of success or other wise (if I should just toss it as useless junk) I would greatly appreciate the info. Thanks for all the good info on this list, T.J. 73 KC8LTS 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 the Yahoo! Terms of Service.
Re: [Repeater-Builder] Mobile Duplexer Question
T.J. wrote: I acquired a Phelps Dodge 636 3/3 mobile duplexer tuned for TX freq. of 163.8xxx and a RX freq. of 167.5xxx. What I was wondering was if this could be tuned down into the ham band with any success for a mobile repeater using some hand held radios. I was looking in my Tessco catalog and saw that this unit resembles the RFS Celwave 636-6A-3/3 with specifications of: Freq. range 164-174 Mhz, max power 50 watts, min. separation 4.5 Mhz, There's your answer right there-4.5 Mhz is bigger than the entire 2M ham band. No, it's not practical to rebuild them to handle a narrower split. If you want a portable/mobile repeater, you should look towards UHF. The in/out spacing on 2M doesn't make it easy to do anything portable. On UHF however, the whole thing, including duplexer and power supply, can be put in a desktop-size box, about the size of a full size HF rig. -- Jim Barbour WD8CHL 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/
RE: [Repeater-Builder] Mobile Duplexer Question
Our local ARES group put together a portable 2m repeater... it is a 6 ft rack cabinet disguised as a fly-away case. Un-plug the power, and feedlines, buckle the sides on and you are ready to go... just don't forget the 6 guys needed to move it. The Vertex can be re-programmed with a laptop... but the cans are another matter. Crude tuning can be done with a ht and SWR/power meter. We used this same repeater when the fruit-loops flew that airplane into the Pentagon. It performed very well, just not my idea of portable. I saw several FEMA boxes that had been retired on eBay a while back.. minus the radios. You might try looking in the industrial radio section for a cheap building block to start with. The box was approx 14 inches square, and about 12 inches deep. Good luck on your project.. mike -Original Message- From: Jim B. [mailto:[EMAIL PROTECTED] Sent: Monday, October 18, 2004 3:45 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mobile Duplexer Question T.J. wrote: I acquired a Phelps Dodge 636 3/3 mobile duplexer tuned for TX freq. of 163.8xxx and a RX freq. of 167.5xxx. What I was wondering was if this could be tuned down into the ham band with any success for a mobile repeater using some hand held radios. I was looking in my Tessco catalog and saw that this unit resembles the RFS Celwave 636-6A-3/3 with specifications of: Freq. range 164-174 Mhz, max power 50 watts, min. separation 4.5 Mhz, There's your answer right there-4.5 Mhz is bigger than the entire 2M ham band. No, it's not practical to rebuild them to handle a narrower split. If you want a portable/mobile repeater, you should look towards UHF. The in/out spacing on 2M doesn't make it easy to do anything portable. On UHF however, the whole thing, including duplexer and power supply, can be put in a desktop-size box, about the size of a full size HF rig. -- Jim Barbour WD8CHL Yahoo! Groups Links 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/
