Re: [Repeater-Builder] duplexer pages
Don't know about txrx. but tell me where you found Sinclair, also I have tuned Wacomms the txrx should not be much different. Bruce. KD4BOH. - Original Message - From: "John Place" <[EMAIL PROTECTED]> To: "Repeater-Builder" Sent: Saturday, May 07, 2005 10:54 AM Subject: [Repeater-Builder] duplexer pages > Was looking at the site and looking down at the duplexer tuning sheets > for the different ones, Wacomm, Sinclair, etc., but didn't see anything > for tuning the txrx series. Nobody have any? > > > > -- > No virus found in this outgoing message. > Checked by AVG Anti-Virus. > Version: 7.0.308 / Virus Database: 266.11.6 - Release Date: 5/6/2005 > > > > > > > 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/
Re: [Repeater-Builder] Micor mobile transmitter
Thanks Eric and Brian for the info. I've been able to run it for 10 yrs @110 watts on 145.270 without any problems in an air conditioned environment. But I'm moving it to a remote location without a/c. I guess I will leave it as is, as I need the power as much as I can get. No duplexer on this machine. Wide area crossband 8 rx site system. Thanks again guys, Bruce KD4BOH. - Original Message - From: "Eric Lemmon" <[EMAIL PROTECTED]> To: Sent: Tuesday, May 10, 2005 8:26 PM Subject: Re: [Repeater-Builder] Micor mobile transmitter > Bruce, > > Although you can disconnect half of the four final transistors and change > the matching components appropriately to have a 50 watt PA, it's better to > simply exchange the 100W amplifier board for a lower power board. I'm > guessing that you could probably find someone to swap boards with, maybe > even make a few bucks in the deal.. > > It is not a good idea to reduce either the drive level or the PA supply > voltage to achieve a lower power output, because the PA can become > unstable. A solid-state PA is normally designed to present a stable > source impedance which, in basic terms, is directly proportional to supply > voltage and inversely proportional to PA current. Reducing the drive > level will reduce PA current, thus raising the apparent PA source > impedance and causing a mismatch with the load impedance- usually the > reactive input impedance of a duplexer. This is not good, and is an > invitation to instability. Reducing the supply voltage has the opposite > effect on the apparent PA source impedance. > > If you have the requisite test equipment and time, you may be able to > adjust both the drive level and the PA supply voltage to achieve stability > at a lower power output level. This is a lot of work, and may be much > more work than simply replacing the PA board. > > 73, Eric Lemmon WB6FLY > > brucenanney wrote: > >> What is the best way to reduce power on a 100 watt micor mobile for >> repeater use? I have reduced the voltage in to 12.8 volts and have >> developed a cooling system on the P.A. deck that has constant air flow >> over the circuit board as well as the the heatsink. >> Thanks, Bruce KD4BOH. >> >> >> Yahoo! Groups Links >> >> >> >> > > > > > > > > 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/
Re: [Repeater-Builder] Repeater Desense
I had an arx270 to slowly burn the cap out @ the feed point of the antenna. They will not handle 100 watts @ feed point on continuous duty. I contacted Cushcraft and they sent me a new cap at no charge. I use it home now, no repeater use. Bruce, KD4BOH. - Original Message - From: "Eric Lemmon" <[EMAIL PROTECTED]> To: Sent: Thursday, May 12, 2005 3:41 PM Subject: Re: [Repeater-Builder] Repeater Desense > Bob, > > The most recent instance was with a Cushcraft ARX-270 2m/440 antenna. I > watched this antenna being assembled, and I can state that there was no > corrosion, maladjustment, or looseness involved. We used that antenna > briefly > for a 2m repeater simply because it was already in place, and we had a > special > event to cover. A Motorola RKR-1225 repeater was hooked to it using > LDF2-50 > Heliax feedline. When the Cushcraft antenna wouldn't work without major > desense, I swapped it for a Sinclair SRL-222 dipole, which worked > perfectly. > > 73, Eric Lemmon WB6FLY > > Bob Dengler wrote: > >> At 5/12/2005 12:37 PM, you wrote: >> >Yes. Many repeater receivers are simply not well enough shielded to >> >keep the TX from leaking into the RX box. Even some commercial >> >repeaters will suffer desense if 100% shielded feedline is not used. I >> >have seen serious desense occur when a dual-band (2m/440) antenna is >> >used on a repeater, due to the uneven gain versus frequency response of >> >many such antennas. >> >> A narrowband antenna by itself will not generate desense. Your problem >> was >> probably due to corrosion, dielectric breakdown, or some other cause >> related to poor construction/materials in the amateur grade antenna. >> >> I would like to know what model antenna this was though, since I have yet >> to see any desense problems with my Comet antennas. >> >> Bob NO6B >> >> >> Yahoo! Groups Links >> >> >> >> > > > > > > > > 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/
Re: [Repeater-Builder] Time-Out-Timer Length
Thanks Eric for the reply. It is a VHF 110 watt mobile that was used in medical field. model #173RTN3100B I have converted it to a vhf tx with a uhf rx. It goes out in the county on a water tower. It rx my uhf control station. The 8 channel voter hub rx my remotes from the other county water towers. The hub sends to the control on a split of more than 15 mhz. no duplexers on this system, just one filter. It works great as long as I can keep the audio levels smooth. Anyway, that gives you an idea of what I am doing. So I'm just trying to put a t.o.t. on the tx because it is a 30 minute drive to it if locks up. Thanks Again, Bruce KD4BOH. - Original Message - From: "Eric Lemmon" <[EMAIL PROTECTED]> To: Sent: Monday, May 30, 2005 7:16 PM Subject: Re: [Repeater-Builder] Time-Out-Timer Length > Bruce, > > What model radio is the TLN1361A used in? I did not find that number > listed on MOL. > > Most rules require a 3 minute maximum transmission unless other controls > are available; what drives your need for such a long interval? Just > curious... > > 73, Eric Lemmon WB6FLY > > brucenanney wrote: > >> Does anyone know how to lengthen a TLN 1361A T.O.T. from Motorola? >> The one I have is 1 minute, I need it to do 10-15 minutes. >> >> Thanks, Bruce KD4BOH. >> >> >> Yahoo! Groups Links >> >> >> >> > > > > > > > > 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/
Re: [Repeater-Builder] Time-Out-Timer Length
Eric and who ever is interested, The T.O.T. I have done some reverse engineering on it. There is 120mfd cap. in the bottom of the can. If you increase it to 340mfd, it will lengthen to about 7 minutes. I think this will be enough for what I'm trying to do. I could increase it more , but there is not enough room for a larger cap. Thanks Bruce KD4BOH. - Original Message - From: "Eric Lemmon" <[EMAIL PROTECTED]> To: Sent: Monday, May 30, 2005 7:16 PM Subject: Re: [Repeater-Builder] Time-Out-Timer Length > Bruce, > > What model radio is the TLN1361A used in? I did not find that number > listed on MOL. > > Most rules require a 3 minute maximum transmission unless other controls > are available; what drives your need for such a long interval? Just > curious... > > 73, Eric Lemmon WB6FLY > > brucenanney wrote: > >> Does anyone know how to lengthen a TLN 1361A T.O.T. from Motorola? >> The one I have is 1 minute, I need it to do 10-15 minutes. >> >> Thanks, Bruce KD4BOH. >> >> >> Yahoo! Groups Links >> >> >> >> > > > > > > > > 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/
Re: [Repeater-Builder] New antenna install ? Any tips ??
Hello there. I weather proof two different ways. I use good military type caulk strips then wrap with 33+. This is what I use when I'm not planning on taking the connecter off, such as a hard-line connecter. The second is, when I'm going to be taking a connection apart, I use 3M Scotch 23 rubber splicing tape , 2" wrap then put 33+ on top of it. The 3M adheres to its self and leaves the connecter clean of residue after it taken off. It's to take off too. Just cut each side of the wrapped connecter with a razor knife and peal it like a banana. Scotch makes some good products. I' m not advertising, just proven experience of over 25 years. Thanks, Bruce KD4BOH. - Original Message - From: "Chuck Kelsey" <[EMAIL PROTECTED]> To: Sent: Saturday, June 11, 2005 5:33 AM Subject: Re: [Repeater-Builder] New antenna install ? Any tips ?? > Glad you mentioned weatherproofing. I should have, since I'm picky about > it. > > Tape --- Scotch 33+ is your best friend. Don't use an off-brand. I buy it > by > the box. It's never let me down. > > Chuck > WB2EDV > > > > - Original Message - > From: <[EMAIL PROTECTED]> > To: > Sent: Saturday, June 11, 2005 12:18 AM > Subject: Re: [Repeater-Builder] New antenna install ? Any tips ?? > > >> >> Perhaps arrange for a Native American rain dance -- there's something >> about >> installations made during rotten weather. Really! >> >> Failing that, pay close attention to your jumper connects. I like to >> dab >> a >> wee bit of clear silicone grease on the threads (not pins) as an >> anti-oxidant. >> Caution on tightening -- too much wrenching can deform the coupling & >> make >> 'em prone to leakage. >> Avoid cheezy tape from the dollar store; pay a little extra for the good >> stuff. >> /. >> >> k9jac1 wrote: >> Is there anything we should do to the new antennas before they are >> installed >> on the tower ? Paint, Seal, Waterproof, Start on fire .. >> >> >> > > > > > > > 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/
Re: [Repeater-Builder] Re:coax notch
Can the notches be made for 440 with 7/8" heliax? I need to notch out 442.675 from getting into 449.975 and 449.950. Can notches be made to do this? Thanks, Bruce KD4BOH - Original Message - From: "Matt Beasant" <[EMAIL PROTECTED]> To: Sent: Sunday, June 12, 2005 5:18 PM Subject: [Repeater-Builder] Re:coax notch >I should add that we ended up screening the tops of our coax stubs as the > coupling between them was considerable. It made a big difference screening > the tops. > > All we did was get some cardboard tube, cover it in tin foil and bond it > to > earth. > > Matt > - Original Message - > From: <[EMAIL PROTECTED]> > To: > Sent: Sunday, June 12, 2005 7:02 PM > Subject: [Repeater-Builder] coax notch > > > > sorry here is the link to the site.bob > > > http://www.qsl.net/kf6yb/duplexer.html > > ___ > Get Juno Platinum for as low as $6.95/month! > Unlimited Internet Access with 250MB of Email Storage. > Visit http://www.juno.com/bestoffer to sign up today! > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > ___ > How much free photo storage do you get? Store your holiday > snaps for FREE with Yahoo! Photos http://uk.photos.yahoo.com > > > > > > 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/
Re: [Repeater-Builder] Water Tower Humidity
Air flow is the key in most of it. I have a 125 watt transmitter at a remote site at the bottom of a water tower. It sets under the tank where it gets water dripping on it in the summer mornings. It is mounted in a home made aluminum box 2'x2'x28" with 3/4" Styrofoam insulation. I put a 4" vent fan in top of the box running all the time. It has vents on 3 sides down low plus the cooling fans on the equipment. No problem with humidity, But the transmitter heatsink temp at close proximity to the final was pushing 125 degrees. So my problem was recirculating warm air inside the cabinet. I cut an 8" whole in the 4th side where I had no vent. I mounted a high volume, high speed, 8" fan and it comes on when the transmitter is keyed. This floods the cabinet with fresh air and drives out the heat. It dropped the temp 15 degrees. I'll just have to watch it in the winter time about being too cool. Hope this helps. Bruce. KD4BOH. - Original Message - From: "Mark A. Holman" <[EMAIL PROTECTED]> To: Sent: Sunday, June 19, 2005 8:03 PM Subject: Re: [Repeater-Builder] Water Tower Humidity >I was thinking on the order which is solar powered charger & supply like >say > a batch of muffin fans from the computer P/S ? I heard something like > that > some time back to cool the attic to a house besides free electricity & > environmentally friendly. > > as to humidity problem, I would go to a place that sells dehumidifiers ( > around $130.00 ) the GE model has a hose attachment @ the bottom of the > tank > and run a drain tube on the floor to the outside. pvc flex tubing or cheap > water pipe at home builders supply would work, or a plain garden hose > would > work. > > just some thoughts ... > > Mark A. Holman AB8RU ARRL Life Member > [EMAIL PROTECTED] > > - Original Message - > From: "Joe" <[EMAIL PROTECTED]> > To: > Sent: Sunday, June 19, 2005 7:18 AM > Subject: Re: [Repeater-Builder] Water Tower Humidity > > >>I am involved in planning a similar installation. The other problem is >>that the base gets extremely hot in the summertime. I was thinking of >>connecting a clothes dryer vent hose to one of the unused entry ports that >>the coax usually gets routed through the wall. (The flexible solid >>aluminum type, not the cheap stuff). Then, air could be drawn from the >>outside to cool the cabinet and keep the humid air out. I would control >>the fan in the cabinet with a thermostat to keep it warm in the >>wintertime. >> >> Joe >> >> Chris <[EMAIL PROTECTED]> wrote: >>> Hi all! >>> I have the opportunity to place a UHF repeater into the base of a >>> water tower which is quite high. Comes with all the bells and >>> whistles and would be an excellent site. However, it is quite humid >>> inside and I'm afraid the repeater will get condensation buildup. >> >> >> >> >> >> Yahoo! Groups Links >> >> >> >> >> >> >> > > > > > > > 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/
Re: [Repeater-Builder] C3I audio delay board
Thanks for the Info, sounds like I need to upgrade. Bruce KD4BOH - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, July 04, 2005 1:50 PM Subject: Re: [Repeater-Builder] C3I audio delay board Hi Bruce, > I have a C3I audio connected to a Cat 300dx. > As you increase the delay there a hiss that > is heard. If you turn the delay off, the hiss is > silent. Any Ideas? That audio delay module uses two cascaded Reticon RD5108 bucket-brigade audio delay chips. Bucket-brigade technology has been obsolete for many years, replaced by better schemes. The chips have a poor signal-to-noise ratio, and cascading them (for longer delay) makes it worse. That's why you hear the hiss. You can't do much about it. Your board is a copy that C3I made of the original S-COM Audio Delay Module. Just as well; the S-COM Digital ADM that came later was a much better product. The design of the DADM is now owned by Integrated Control Systems, which also sells the DADM. 73, Bob Bob Schmid, WA9FBO, MemberS-COM, LLCPO Box 1546LaPorte CO 80535-1546970-416-6505 voice970-419-3222 faxwww.scomcontrollers.com YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. 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] GM300 power adjustment limit?
I can tell you what I've came up with on mine and it might help. I have M120's as link transmitters, the boards are basically the same. If I turn my power down below 8 to 10 watts it starts acting up, spurs and changing power out each time you tx out. I keep my power set at 12 to 15 watts and seem to do fine. I mounted it and VHF radius 100 on top of 12 amp Astron. I have 5 of these units running in repeater system. Some of them have ran as long as 8 years with out being touched. When I did have problems it was power supply problems not radio problems. I also put 4" fan blowing across the fins. Hope this helps. Bruce KD4BOH. - Original Message - From: "Ken" <[EMAIL PROTECTED]> To: Sent: Tuesday, July 12, 2005 9:17 AM Subject: [Repeater-Builder] GM300 power adjustment limit? >I have a 40 watt UHF GM300 I would like to tune down to 10 watts? Is > this a safe level to set to on the 40 watt units? I heard that if the > power level is set too low it will cause spurs? What is the lowest > power level I can set the amp to? > > Thanx for reading. > Ken > > > > > > > > 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/
Re: [Repeater-Builder] IOTA Switched Power Supply and Noise?
Does anybody have a web site to look at IOTA power supply? I need to find some to replace my power supplies in the future. Bruce KD4BOH.- Original Message - From: "Joe Montierth" <[EMAIL PROTECTED]> To: Sent: Wednesday, May 25, 2005 2:22 PM Subject: Re: [Repeater-Builder] IOTA Switched Power Supply and Noise? >I have one of the 75 amp supplies working at a remote > site. We have not seen any noise from the unit, but > our equipment is all VHF and UHF, haven't checked it > down in HF, but at UHF we have seen no problems. We > have 20 UHF RX's and 6 VHF and have not seen any > degradation. > > These IOTA's run much cooler than the analog Astron's, > and are much smaller. I will probably be changing out > all of the Astrons to these in the next few years, as > conditions warrant. > > Joe > > --- Nick Papadonis <[EMAIL PROTECTED]> wrote: >> Hi Folks, >> >> I'm considering purchasing a 45A IOTA Switched Power >> supply to power a UHF Micor and am concerned about >> switch PS noise. >> >> Has anyone tried these supplies with UHF radios? Is >> noise experienced? >> >> Insight greatly appreciated. Thanks. >> >> -- >> Nick KB1GZN Boston, MA >> >> >> >> > > > > > __ > Do you Yahoo!? > Yahoo! Small Business - Try our new Resources site > http://smallbusiness.yahoo.com/resources/ > > > > > > 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/
Re: [Repeater-Builder] Re: Rx Combiner
OK skipp here goes, TX freq. is 442.675. Rx freq. are 447.675, 449.075, 446.775, 449.875. TX antenna is a set of stacked 6 element beams pointed at remote 2 meter TX site. Is 30' side mounted under rx antenna inwhich is on top of tower. Rx antenna is G6-2/70 R. I have Bp filter on 447.675. Tx is @ 40 watts. If I need to put Bp on other receivers I have them. They are synclairs. All radios are Micors. Thanks Bruce. - Original Message - From: "skipp025" <[EMAIL PROTECTED]> To: Sent: Tuesday, August 02, 2005 4:37 PM Subject: [Repeater-Builder] Re: Rx Combiner > > Sure, I'll tell you how right here... just tell me > the approx frequencies of your receivers and what you > plan to use as your tranmitting antenna (ie how far > away it is on the tower). > > It would also be nice to know what type of receivers > you're using. > > Your turn... > skipp > skipp025 at yahoo.com > www.radiowrench.com > >> "brucenanney" <[EMAIL PROTECTED]> wrote: >> Anybody got a good idea for building a combiner for UHF receivers. >> Need to put 4 Rx on one antenna. Thanks, Bruce. > > > > > > > > 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/
Re: [Repeater-Builder] Re: receiver combining (Was Digest Number 3263)
OK Al, I am using 75 ohm split on two Micors with a preselecter on each. Seems to work rather well. I bought a CATV 10 db adjustable gain splitter from Radio Shack several years back and converted it to 12 volt to run on battery back-up, but never had the need to use it till now. Sounds like we're along the same thinking on this. So we take the preselecters off the Micors, put on the RS 4-way splitter, gain set to over come loss. What about jumpers, 75 or 50 ohm ? Does it really matter, and do they need to be 1/4 wave length of the freq. they are hooked to ? Thanks, Bruce KD4BOH. - Original Message - From: "Al Wolfe" <[EMAIL PROTECTED]> To: Sent: Thursday, August 04, 2005 12:56 AM Subject: [Repeater-Builder] Re: receiver combining (Was Digest Number 3263) > >> At 8/3/2005 06:14 AM, you wrote: >>>Bruce, >>> One common method of combining two receivers is to use a coax tee at >>> the >>>antenna feedline and 1/4 wave pieces of 75 ohm coax from the tee to each >>>receiver. This can be expanded to four receivers using six pieces of 75 >>>ohm >>>coax, but probably isn't worth the effort. >> >> But what if the RXs have high Q filters in the front-end that look like >> an >> open at the other RX's freq.? The 1/4 wave transformer will turn that >> open >> into a short at the T, shorting out the RF that otherwise would go to the >> other RX. >> >> Sounds unlikely? I know of one group that did this to their repeater a >> while back. The result was a deaf repeater providing a disservice to the >> amateur community for many years. >> >> Use a power splitter, either CATV or 50 ohm (Mini Circuits). The >> port-to-port isolation will save you much grief in the long run. >> >> Bob NO6B >> > > > Bob, > If it was the truly the case that the receivers had a high impedance > at > off channel frequencies then you could just hook them all together in > parallel and be done with it. However, most receivers have very low > impedances off-channel. (Also, few front ends are ever actually 50 ohms > resistive anywhere for that matter.) Because of the low impedance of > off-frequency front ends, receivers with noise blankers usually have their > two receiver inputs in series and the blanker receiver must be tuned > several > mhz. away from the main channel to not cause the sensitivity to be > compromised. > >I suspect that if the group with the deaf repeater had added a few > inches of line to the other user's receiver their problem would have been > solved. > >I have aircraft receivers from the FAA with two antenna jacks, one in > and one out. Several receivers can be daisy chained together this way. The > last receiver has a shorted "N" connector on the antenna out port. > Effectively, all the different receivers' first RF coils are in series > with > each other. > >The 1/4 wave, 75 ohm coaxes were/are commonly used with DFE (dual front > end) receivers or stations with two receivers. > >As you say, however, the splitter is usually a superior method of > combining receivers from one feed. The ones from MiniCircuits provide 20 > db > or more isolation between ports and the lengths of feedline from the > splitter to the receiver isn't critical. The complex reactance's of the > receiver front ends are isolated from each other. A dead short across one > of > the output ports will have minimal effect on the other ports. > >Another benefit of the splitter and its isolation came to bear in a > situation I had several years ago where we had several UHF receivers > sharing > a common antenna using the 1/4 line technique. Very strong signals on one > receiver could often be heard on another receiver in the cluster. Turned > out > that some of the mixer injection from one receiver was getting back out > though the RF stage and into another receiver. A splitter with 25 db of > isolation between ports got rid of the problem. > > 73, > Al, K9SI > > > > > > > > > > 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/
Re: [Repeater-Builder] Re: receiver combining
OK on RS amp. That is why it has laid on the shelf for so long. A preselecter is Motorola's term for their internal preamp. It has 3 to 9 db of gain and they have tunable pass notch in them to narrow it to freq. your on. They are usually not very good for broadband window. I have never heard mini circuit company, I'll have to check them out. Alot of people on here refer to them. Thanks, Bruce KD4BOH. - Original Message - From: "Al Wolfe" <[EMAIL PROTECTED]> To: Sent: Thursday, August 04, 2005 9:23 AM Subject: [Repeater-Builder] Re: receiver combining > Bruce, >I don't think you will be happy with an amplified splitter from Radio > Shack. Your concept is valid but the RS amp will probably have much too > high > a noise figure to be useful for off the air use in repeater service. >I would be leary of any Radio Shack device hooked to an outside > antenna, > especially around a repeater site where you have frequent lightning > currents > to deal with. >Not sure what you mean by preselectors in front of the Micors. Why do > you need them? Are you talking about a duplexer? Micors are generally > pretty > bullet proof by themselves. You probably will want some sort of > pre-selection between the antenna and any preamp. The DCI Bandpass filters > work well for this. >I have had good luck with the AAR preamps. Others swear by Angle > Linear. >As far as jumpers from the splitter to the receivers, it probably makes > little diference as to what impedence to use. If you are using a TV type > splitter then it is probably easier to use a quality 75 ohms cable with > the > "F" connectors. Since this is a receive set up and you won't be > transmitting > through them, you can and should use the 100% shielded coax for the > jumpers, > the most common being foil shielded. You should be able to use any > practical > length for them. Please don't use the foil shielded coax for any duplex > operations, though. > > 73, > Al, K9SI > > >> Date: Thu, 4 Aug 2005 02:06:45 -0500 >> From: "Bruce Nanney" <[EMAIL PROTECTED]> >> Subject: Re: Re: receiver combining (Was Digest Number 3263) >> >> OK Al, I am using 75 ohm split on two Micors with a preselecter on each. >> Seems to work rather well. I bought a CATV 10 db adjustable gain splitter >> from Radio Shack several years back and converted it to 12 volt to run on >> battery back-up, but never had the need to use it till now. Sounds like >> we're along the same thinking on this. >> So we take the preselecters off the Micors, put on the RS 4-way splitter, >> gain set to over come loss. What about jumpers, 75 or 50 ohm ? Does it >> really matter, and do they need to be 1/4 wave length of the freq. they >> are >> hooked to ? Thanks, Bruce KD4BOH. > > > > > > > > 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/
Re: [Repeater-Builder] Re: Static Cling (was - polyphaser)
Ok, There putting strips on the bottom of Target and Wal-Mart shopping carts to keep static down when a customer grabs the handle. So why wouldn't this work well on a vehicle? Thanks, Bruce KD4BOH. - Original Message - From: "Kevin Custer" <[EMAIL PROTECTED]> To: Sent: Monday, January 02, 2006 7:46 AM Subject: Re: [Repeater-Builder] Re: Static Cling (was - polyphaser) > [EMAIL PROTECTED] wrote: > >>Hey, ya drag your feet on the carpet .. aren't you thus 'connected' ?? >>Shockingly, no. >> > Interesting that this would come up... Last year, before installing a > whole house furnace humidifier, I got zapped every time I reached for a > light switch (screws are grounded). Many times it would draw an arc of > 1/4 inch or more. Just for the heck of it, I did a test. I put on my > shoes and drug my feet across the carpet and with a NE-2 neon bulb, > touched the screw on a convenient lamp switch. Many times I would build > up enough static electricity that I could make the bulb burn for about a > second, and sometimes it would snap (arc across?). > > I took one of the Static Busters and put the end that gets mounted in my > mouth. I did the test again, and was very surprised that I couldn't > build up enough charge to make the bulb light. > > Kevin > > > > > > 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/
Re: [Repeater-Builder] Repeater Funding
Just an idea, I got $3000.00 of Homeland Security money by going thru local EMA office that had access to alot of different grants. The catch is: Having someone that knows what to say and how to write the grant and be involved with a Government funded Entity. Example: I got 5 dual-band antennas and 500 ft 1/2" hardline for 5 remote receive sites that was put on water towers. Only catch, If I take my system down I have to leave the antennas and hardline. Otherwise I have total control. The repeater system does belong to me. But just thought this might give you an idea. Bruce KD4BOH - Original Message - From: "goldvetter" <[EMAIL PROTECTED]> To: Sent: Wednesday, January 04, 2006 11:23 AM Subject: [Repeater-Builder] Repeater Funding We have a repeater that needs to be gone through and replaced. Our club has very little funds to replace the equipment. What if any kind of funding is out there to help defray the costs of the new equipment? Thanks in advance, Steve KCØTJH 73's 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/
Re: [Repeater-Builder] Motorola Micor Mobile
Make sure the tx/rx antenna switch is working properly and check the power set board in it. It can shut down the P.A. deck if not working properly. Bruce, KD4BOH. - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Thursday, January 05, 2006 3:17 PM Subject: Re: [Repeater-Builder] Motorola Micor Mobile In a message dated 1/5/2006 2:51:14 PM Central Standard Time, [EMAIL PROTECTED] writes: I have a Micor mobie that is getting power to the exciter but not showing and power out of the PA. I think the finals are good but could be wrong. Not an electronic genius. Thanks Any help would be appreciate Hi there! Been there, done that! You may need to check the bandpass filters. The exciter should be around .4-.5 watts out, and the bandpass may not be "passing" especially at ham freqs! As an old friend said, "Tune for max smoke" on both filters, but remember that's how Moto kept the spurs in check! Make sure you double check for Clean Output! 73, Brian YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.