Re: [Repeater-Builder] Dielectric diplexer
Bill, Looks like those cavities will bolt together end to end. All four would make a nice single 6m cavity. The 3 1/8 elbows look to be good quality and are always in demand for high power FM radio work. Keep these and their inner bullets. The 3dB couplers look to be machined from a single block, so theycould be converted to stripline filters for 220 if you can obtain some 3 1/8 to N type adaptors. Ian G8PWE - Original Message - From: Bill Isom To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 12, 2010 7:41 PM Subject: Re: [Repeater-Builder] Dielectric diplexer I have a picture of the unit. It is on a roll around frame, fed with 3 hardline, and has four cavities. The cavities look to be copper, about 10 dia and a little over 2' tall. Two Bird looking wattmeters are in the photo and there is a massive looking dummy load. Any ideas about converting the 3 hardline to something usable? I figure if I can't get it to 220, those copper cavities will make one heck of a still. 73 Bill N4XIR -- From: Glenn Little WB4UIV glennmaill...@bellsouth.net To: Repeater-Builder@yahoogroups.com Sent: Wed, August 11, 2010 10:00:04 PM Subject: Re: [Repeater-Builder] Dielectric diplexer I disassembled one for channel 4. The cavities were about 3 feet in diameter. I salvaged the plungers for the INVAR rods. The diplexer was mounted on a huge roll around aluminum frame. The cavities were connected with 3 inch ridge line. There were four cavities, two fir video and two for audio. There was a 5 KW reject load attached as well as two power meters for 3 in line. The slugs for these look like Bird 43 slugs and will fit into a Bird 43 meter, however, the coupling is wrong for a standard Bird line section, so, the slugs read very low, ie, 500 Watts pins the meter with a 25KW slug installed. Have you seen what you are getting? A friend of mine made fuel tanks for his generator from the channel 4 cavities. I suspect that you could get the cavities to 220 MHz, At 25KW, I suspect that your cavities are also fed with 3 inch rigid line. 73 Glenn WB4UIV At 07:37 PM 8/11/2010, you wrote: I have just been told I am about to receive a dielectric brand diplexer rated at 25000 watts on 191 Mhz from a analog TV station. I feel a little bit like the dog that catches the car he is chasing. Now that I have it, what can I do with it? Any ideas? Can it go to 220? Does anyone have any experience with these? Thanks Bill N4XIR Yahoo! Groups Links
Re: [Repeater-Builder] Re: Invar Rods
Just a thought, Why dont you turn the pistons around to give you a longer reach? Ian G8PWE - Original Message - From: Burt Lang b...@gorum.ca To: Repeater-Builder@yahoogroups.com Sent: Saturday, July 17, 2010 4:08 PM Subject: Re: [Repeater-Builder] Re: Invar Rods What diameter are the rods? The older Sinclair VHF Hi cans used 5/16in diameter whereas the newer cans used 1/4 in daiameter. burkleoj wrote: Glenn, I need 6 of them for a Sinclair duplexer that I have. Someone cut the rods off when it was originally on a commercial frequency. The rods in my duplexer are so short that it will not tune below 147 MHz before they disappear inside the top of the cavity. Very common when the frequencies are in the high 160s I can get some dimensions for you to see if the ones you have may work. Thanks, Joe - WA7JAW You can buy invar rod material from some metal suppliers but you won't like the price. It normally comes in 12ft lengths but the dealers will cut it in half in order to ship UPS. The last time I bought some (around 1990) the price was $30/lb. The dealer was Diezel (or Diesel) Metals on Long Island somewhere. I still have some left from that order. FYI Invar is an allow consisting of exactly 35.16% nickel with the remainder iron. It is magnetic and will corrode in a damp environment leaving a green rust on the surface. Burt VE2BMQ Yahoo! Groups Links
Re: [Repeater-Builder] Mask filters?
Kris, These filters are constant impedance designs so the transmitters unwanted sideband power gets dumped into a load on the Hybrid port. This also helps with group delay at edges of the filtered response. ... cant see why a ham would make a filter with twice as many cavities than needed, just to keep SWR low out of band.. The only possible use would be as a combiner for two repeater transmitters because one hybrid port acts as a wideband input. Problem is, if you are on 2m with two repeaters 60kHz apart each resonator has to be pass F1 and short F2. mange tout Ian G8PWE - Original Message - From: Kris Kirby k...@catonic.us To: Repeater-Builder@yahoogroups.com Sent: Monday, February 22, 2010 6:21 PM Subject: [Repeater-Builder] Mask filters? In the commercial world of broadcasting, there is a hybrid filter used called a mask filter. The mask filter is two -90 degree hybrids, a dummy load, and a pair of bandpass cavities between them. They suppress sidebands and keep the TV transmitter's radiation within the 6MHz channel. Has anyone heard of a similar concept used for filtering amateur repeaters? -- Kris Kirby, KE4AHR Disinformation Analyst Yahoo! Groups Links
Re: [Repeater-Builder] Re: Sinclair Dual Circulator Help
Wullie, Having moved many of these particular devices from 142 mhz to 145 mhz I would follow this proceedure. Check it on its original frequencies for insertion loss and isolation. The Pass band on 1db per division should be around 20 mhz. The isolation plot will be much more narrowband ..around 1 Mhz and there should be two identifiable notches around the original operating frequencies one for each section. Tap the unit gently whilst measuring insertion loss on 1dB per division. If it is microphonic gently tap each multiturn capacitor with a plastic probeto find which one is dirty. Then take all of the pistons out of all the capacitors (5) and clean the threads with isopropl alchohol. Also clean the threads inside with a cotton bud. Return the caps to their original positions and check for microphonics again. If the circulator is still microphonic, Identify which section is faulty. Take off the sinclair label and apply a bead of superglue releasant to the round thraded plate. Make a spanner that has two 1/8 steel pegs 1/4 long at the right separation. Tighten the plate 1/4 turn clockwise and re-check microphonic performance. You may be lucky and not need to repair your circulator but most of the 142mhz ex british gas units were OK on dismantling but have been roughly treated at hamfests etc. When everything is working for you can I suggest some tape over the tuning holes to keep the dust out? Ian G8PWE - Original Message - From: Wullie wullie...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Saturday, June 13, 2009 10:10 AM Subject: [Repeater-Builder] Re: Sinclair Dual Circulator Help --- In Repeater-Builder@yahoogroups.com, Eric Lemmon wb6...@... wrote: Wullie, If the isolator was made for a frequency that is more than 4 MHz away from your 2m transmit frequency, it cannot be tuned to work properly that far away from its design frequency. No matter who makes the unit, each isolator (which is called a circulator if dummy loads are not provided) is made-to-order for a specific frequency. The catalog descriptions of such devices are very misleading, since the description often says something like, 136-174 MHz, which means only that the company can manufacture an isolator to work within that range; it does NOT mean that an isolator can be field-tuned to any frequency within that range. A very informative article on this topic is found here: www.repeater-builder.com/antenna/ant-sys-index.html#iso-cir Several years ago, I acquired more than a half-dozen Sinclair dual isolators that were part of a military VHF radio system. Some of these isolators were made to work around 138 MHz, while others were made to work around 163 MHz. I quickly discovered that none of them would perform properly at 2m. I contacted Sinclair and learned that I could have any one of them re-manufactured to a specific 2m frequency for $250- about 1/3 the cost of a new unit. The only prerequisites were that the two dummy loads be in good condition, the isolator works properly at the frequency stamped on the unit, and that the case had never been opened since it left the factory. The radio club shipped the used isolator to Sinclair along with a check, and we received a perfect isolator, with a guarantee, in about two weeks. It is still in service. Every time this topic comes up, a few posters claim that they have re-tuned a commercial-frequency isolator to 2m, and further claim that it works perfectly. Baloney! Proper tuning of a circulator or isolator takes a network analyzer, or at least a good spectrum analyzer with tracking generator and a return-loss bridge. There's no way that an isolator can be tuned properly by simply adjusting the caps for maximum forward power. It takes some precision grinding, machining, and lapping to very close tolerances to manufacture a circulator, or to modify it for a new frequency. The magnetic properties of the pole pieces must be carefully adjusted to match those of the ferrites. This is a very exacting process, and it results in a unit that will work properly only over a narrow band of frequencies- usually less than +/- 2%. Nevertheless, there are misinformed people out there who will lead you astray. If you want your repeater to function properly, please have your isolator properly tuned to your frequency. An incorrectly-tuned isolator may SEEM to be working properly, but can be very unstable when the load impedance shifts, and can cause severe damage to the PA or to itself. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Wullie Sent: Friday, June 12, 2009 12:22 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Sinclair Dual Circulator Help Hi All I recently purchased a Sinclir I2210A Dual Isolator for our local 2m repeater. I
[Repeater-Builder] Beer barrel duplexers.
Guys, An update on the beer barrel 2m duplexer project. (please read the embedded .pdf file for background information) http://www.radiohamzone.com/Beer_Barrel_MK3/Beer_Barrel_MK3.htm Ian G8PWE
[Repeater-Builder] 440/ 70cm Duplexers 1.6 mhz shift
Guys, Update on the 70cm duplexer project using surplus Tetra/Dolphin motorised cavities. http://www.radiohamzone.com/DolphinDuplexers/dolphin_duplexers_build.htm Ian G8PWE
Re: Re: [Repeater-Builder] FCC Denies Petition to Utilize 2m Sub-Band for Digita
Ron, A couple of UK repeaters are dual standard d-star / Analogue. Digital/auto/analogue switching is achieved via an embedded suffix in the d-star path description. Its a good way to introduce people to d-star. Analogue users need CTCSS enabled to mute the d-star noise See http://www.ukrepeater.net/index.html Ian G8PWE - Original Message - From: Ron Wright To: Repeater-Builder@yahoogroups.com Sent: Friday, May 09, 2008 1:47 PM Subject: Re: Re: [Repeater-Builder] FCC Denies Petition to Utilize 2m Sub-Band for Digita Joe, I am planning adding D-Star to my analog 2m repeater. I am planning a dual control so if a user has CTCSS then the analog side would work and if no CTCSS then the d-star path would be used. Not a full D-Star approach for we will not be looking for the D-Star formated data, only if you have CTCSS or not. Simple and hopefully can get some interest in D-Star and demo its advantages and disadvantages. The problem is in some areas, like where I am, there are no pairs for D-Star to go on in the 2 m band. We are full and this is the problem in many areas. Also the D-Star ICOM controllers are not like most repeater controllers. They talk to the ICOM repeaters with a Cat-5 cable with serial data giving commands such as ptt, digital audio data, etc. Not the simple get COS/key transmitter. So if doing full D-Star and wanting to get into the gate way, ICOM's IRLP or Echolink, then you need ICOMs controller. Much more complex solved with $. A D-Star repeater can go for $5-10k and this is for what is on the ground. There have been couple analog repeaters converted to D-Star here. This has been the most growth. 73, ron, n9ee/r From: MCH [EMAIL PROTECTED] Date: 2008/05/08 Thu PM 10:45:33 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] FCC Denies Petition to Utilize 2m Sub-Band for Digita You know a lot of this problem could go away of they would only make dual mode repeaters like P25 systems are. Then, you could replace an existing repeater and simply ADD the D-STAR mode to the area. That way, you could have just as many D-STAR repeaters as analog repeaters with the same coverage. Joe M. Ron Wright wrote: Jim, I tend to agree more spectrum is not needed on 2 meters just to accommodate D-Star or any other mode, digital or analog. Many analog boys are also starving for space for their repeaters. D-Star does look for the proper D-Star format to unsquelch as one might say. It does not simply turn on with signal like many analog rigs do. The repeaters and rigs do this. This is why, as you very well know, we use CTCSS...to unsquelch the rcvr when the proper tone rcv'd. The petition to the FCC was an attempt to gain more repeater pairs mainly for D-Star. I am sure the petitioners would have wanted the expansion to go for digital only. I am sure the FCC saw thru this. Another issue popped up about a year ago. An FCC rep made a comment at a forum stating or more like asking if D-Star was really a normal Ham repeater since it delays the digital data and is in a Packet type store and forward mode. The delay is ms. With this in mind there were repeater councils giving out freq pairs which were not in the FCC rules for repeater...145.5-145.800. There were some actually using them. This effort has for the most part gone away. 73, ron, n9ee/r From: wd8chl [EMAIL PROTECTED] Date: 2008/05/08 Thu PM 02:39:00 CDT To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] FCC Denies Petition to Utilize 2m Sub-Band for Digital Repeater Operation Mark Thompson wrote: -- May 7 2008 Ken D. Chafin 3624 Foothill Road #1 La Crescenta, CA 91214 Leon J. Brown 1627 Fair Park Avenue Los Angeles, CA 90014 Re: Petition for Rule Making filed October 10, 2007 snip for brevity The Petition argues that additional spectrum is needed for repeater stations because some amateur repeater stations have begun using certain digital communication protocols, and digital voice operation is incompatible with existing analog operations [because d]igital voice users are unable to determine if the desired frequency is in use by analog users and can inadvertently cause harmful interference to those users. Good. D-Star and other digital voice modes do NOT need more spectrum on 2M. If a digital voice mode does not have some sort of provision for monitoring for non-digital activity, or preventing transmission if there is any, it needs to be redesigned, as it can easily be considered illegal. P25 has it. Jim WD8CHL Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
Re: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote
Paint a polythene cup with your favourite antenna covering. Let it dry and put it into the microwave oven along with a cup of water (to act as a dummy load) Cook for 1 min on max power. If it gets even slightly warm its no good for antennas. er.. can I please have an award for the first cooking recipe to get past the moderator on repeater-builder Ian G8PWE - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 2:44 PM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote I constructed a 6 meter beam some years back, worked like a bomb even at 25ft above ground elevation. To ensure my pride and joy would last a long time I sprayed it with clear Krylon brand spray paint. The antenna was instantly unusable regardless of my efforts to remove the paint, re-tune or otherwise modify the antenna. I later learned that type of paint contained materials with a horible D-Factor. I was never able to use the antenna again, although it remains in my back yard as a reminder. cheers, s. Chuck Kelsey [EMAIL PROTECTED] wrote: Boy, you took a gamble. I'd have been afraid that this action could have either messed up the VSWR or shifted the resonant point of the antenna. Then again, maybe it did and either you don't know that or it wasn't significant. Chuck WB2EDV - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 04, 2008 12:19 AM Subject: [Repeater-Builder] Re: antenna question - Dip It and Scotch Kote Hi Robert, You might get lucky... because they might also have advertised the dip-it as an insulator material, which means someone was hopefully looking at the dissipation factor (aka D-Factor) when the compound was engineered. Time will tell... cheers, skipp georgiaskywarn kd4ydc@ wrote: Someone else told me that after I had put a whole can of dip it on the db408 I showed you. I went back and covered every inch of it with liquid electrical tape. I have had good results in the GA sun with it. 73, Robert KD4YDC
Re: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer
Eric, Thanks for doing that research I see a cable spec MIL-C-17/75G in my latest suppliers catalogue. Is this the new cable to which you refer? Also have you seen any information on connectors for this new cable. Specifically, do you remove the foil before crimping the braid ? Ian G8PWE - Original Message - From: Eric Lemmon To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 12, 2008 5:49 PM Subject: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer The discussion of RG-214/U coaxial cable prompted me to take a look at the current military specifications, and I was surprised to note that a new version of RG-214/U cable has arrived. This new version has a one-mil thick polyester tape with an aluminum coating that wraps around the outer shield, with the aluminum side in contact with the silver-plated shield. I have just created a folder in the Files section of this list, entitled Coaxial Cable Specifications. The Military Specification for RG-214/U cable is MIL-C-17/75F. There is also a copy of Amendment 1 to that specification, which makes it inactive for new design and shows RG-214 to be replaced by M17/190-1. I included a copy of that spec, as well. One might wonder if the new and improved cable is more prone to PIM from dissimilar metals than the original. I intend to upload several other specs soon, including RG-58, RG-213, RG-142, RG-400, etc. Stay tuned... 73, Eric Lemmon WB6FLY
Re: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer
Eric, Again thanks for your splendid research. Looking through the old and new RG214 spec it looks like the Aluminium foil was inserted to improve vertical flame performance. The foil is in the RF cold area behind the 2 shields, however Im sure there are instances where this foil will corrode and introduce increasing intermodulation with age. This is a shame..looks like RG400 is the only way to go with new installs. Regards Ian G8PWE - Original Message - From: Eric Lemmon To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 12, 2008 7:38 PM Subject: RE: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer Ian, That information is a surprise, because the current listing shows MIL-C-17/75F, here: www.dscc.dla.mil/Programs/MilSpec/listdocs.asp?BasicDoc=MIL-DTL-17 No, the MIL-C-17/75F (or 75G, if it indeed exists) are RG-214/U designs. The new cable with the foil-backed polyester layer is identified as M17/190-1. The old RG designations are becoming obsolete, which complicates identification. Since the cable OD has not changed, the same connectors will continue to be used. Although I have no official instruction to follow, my personal feeling is to crimp the foil layer with the shields to ensure intimate contact at each end. I'd sure like to know whose idea it was to add an aluminum layer to a fine cable like RG-214/U! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of IM Ashford Sent: Saturday, April 12, 2008 11:19 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer Eric, Thanks for doing that research I see a cable spec MIL-C-17/75G in my latest suppliers catalogue. Is this the new cable to which you refer? Also have you seen any information on connectors for this new cable. Specifically, do you remove the foil before crimping the braid ? Ian G8PWE - Original Message - From: Eric Lemmon mailto:[EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com Sent: Saturday, April 12, 2008 5:49 PM Subject: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer The discussion of RG-214/U coaxial cable prompted me to take a look at the current military specifications, and I was surprised to note that a new version of RG-214/U cable has arrived. This new version has a one-mil thick polyester tape with an aluminum coating that wraps around the outer shield, with the aluminum side in contact with the silver-plated shield. I have just created a folder in the Files section of this list, entitled Coaxial Cable Specifications. The Military Specification for RG-214/U cable is MIL-C-17/75F. There is also a copy of Amendment 1 to that specification, which makes it inactive for new design and shows RG-214 to be replaced by M17/190-1. I included a copy of that spec, as well. One might wonder if the new and improved cable is more prone to PIM from dissimilar metals than the original. I intend to upload several other specs soon, including RG-58, RG-213, RG-142, RG-400, etc. Stay tuned... 73, Eric Lemmon WB6FLY
Re: [Repeater-Builder] Motorola MSF5000 s/w required?
Dave, You didn't have to upset all the nice people on here... I also have the software..(a paid for copy) Is your machine an exported MSF5000 ie MSF1 ? If so, There is some nice software to turn the machine into a repeater referred to at: www.vfdb.net/vus/dss2/umbau_DSS_DL1XM.pdf Regards Ian G8PWE - Original Message - From: dave_g7uzn To: Repeater-Builder@yahoogroups.com Sent: Monday, February 25, 2008 11:13 AM Subject: [Repeater-Builder] Motorola MSF5000 s/w required? Hi All, In a moment of madness I have bought a Motorola MSF5000 model C64CXB7106B with a view of making a 70cm's repeater out of it. I have downloaded much useful information from this site (thanks lads) but you know what's coming next! In order to change the freqs/pl etc I'm going to need the rssi s/w RVN-4077G. Can anyone help in any way please? Thanks in advance...Cheers Dave UZN please reply direct at [EMAIL PROTECTED]
Re: [Repeater-Builder] DB4062 woes...
Paul, Excellent photos! The only reason these two pieces of metal have began touching each other is that the invar plunger or the silver tuning sleeve have become bent. This could be due to some rough handling of the unitsprobably when you were absent? Personally, I would drill a series of small holes around this top plate to produce a larger hole,cleaning up with a small round file, giving about 1/8 clearance between the plunger and the sleeve. I agree that any kind of heating would ruin the plating.. If the plunger is now free of the tuning knob then perhaps you could slip some heatshrink tubing into the gap and fix it with a heatgun.. Ian G8PWE - Original Message - From: Paul N1BUG To: Repeater-Builder@yahoogroups.com Sent: Wednesday, October 24, 2007 7:36 PM Subject: Re: [Repeater-Builder] DB4062 woes... Progress! Scott, or anyone... I got one of the knobs off. Removing them is not such a big deal as I thought. It turns out the brass insert in the knobs is threaded. They are screwed onto the rods AND soldered. Sheesh! The hole in the top metal end plate of the plunger is indeed just a little bigger than the rod... not much more than .010. Photo: http://www.n1bug.com/cavity2.jpg If there originally was an insulated insert I suspect it was a special item for this application (or at least not hardware store variety). But if there wasn't one then I'm left with the original mystery of why it didn't have this noise problem until fairly recently. So what now? I think I could solder the rod to the top of the plunger without dislodging the whole end plate. Is that a bad idea? Better ideas? Alternatively, I think I could just squeeze some .005 PTFE sheet in that gap, but there isn't enough clearance to allow overlapping the ends at all. Also it might not stay put or hold up well with time and vibration. I still can see no other possible source of the noise/desense in this cavity. Paul N1BUG
Re: [Repeater-Builder] Cable formula
OK, There was a long and detailed thread about z matchers on this group abou a year ago? Lots of interesting stuff about line matching emerged.. dont take my word for it have a look in the archives... I can only describe what I measure and that is cable leakage from a jumper between the transmitter and the duplexer when a DB products z matcher was used. (The z matcher was very nicley made with gold plated piston caps etc.) The cable leakage stopped when the z matcher was removed and the cable length was altered for optimum. Ive just dug out my line stretcher : 874-lk20L constant impedance adjustable line- general radio USA no striped paint here im afraid! Ian Ashford G8PWE - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Saturday, June 30, 2007 3:50 AM Subject: Re: [Repeater-Builder] Cable formula A good quality Z-Matcher has isolation caps on the trimmer ports so I don't think the matcher itself is producing any RF radiation. I don't understand your description of the z Matcher as introducing any mismatch. The mismatch is already there as a result of some disparity between the source, load and cable impedances. All the matcher does is permit you to match the source and cable impedances. In a message dated 6/29/2007 4:40:45 P.M. Pacific Daylight Time, [EMAIL PROTECTED] writes: The z matcher is another option but in my practical experience it makes the jumper radiate RF you spend all that money on RG214/RG400 double silver plated shielding and then deliberatley mismatch it? Ian Ashford G8PWE -- See what's free at AOL.com.
Re: [Repeater-Builder] Cable formula
OK so you have a reel of cable and two connectors to make up the jumper between transmitter and duplexer. The duplexer is tuned using 50 ohm test gear and the transmitter has been optimised into a 50 ohm load. Unfortunatley the output impedance of the transmitter is not 50 ohms and a length of cable to the duplexer will transform this impedance,detuning the first can in the transmit chain. A cable length can be found that minimises this effect this length can be found more easily by measurement than by calculation. I recommend a General Radio line stretcher as your next purchase from flea market/ebay. Using the stretcher an optimum electrical length can be found and copied to jumper length using the sweeper substitution method. All of this work can be done on site using a cheap sweeper and a line stretcher. Alternativley, a ferrite isolator can be put at the can end of the run, however the original posting is not in this area and isolator losses and sag make it an unattractive option. The z matcher is another option but in my practical experience it makes the jumper radiate RF you spend all that money on RG214/RG400 double silver plated shielding and then deliberatley mismatch it? Ian Ashford G8PWE
Re: [Repeater-Builder] bag phone for repeater 911
Look on he positive side. We switched our analogue phone network off 10 years ago and as hams we are still collecting and reusing all that stuff.. like hundreds of feet of rg400 with connectors,erricson and Motorola combiners that can be modified as 440mhz duplexers(they are 3/4 wave at 800mhz) Erricson receivers and transmitters, massive blown Motorola PAs . All this stuff was free or very cheap,as long as you arrange for yourself to be in the right place at the right time...# Ian G8PWE - Original Message - From: Mike Morris To: Repeater-Builder@yahoogroups.com Sent: Tuesday, May 22, 2007 6:17 AM Subject: RE: [Repeater-Builder] bag phone for repeater 911 After the magic date there won't be any analog equipment for your bag phone to talk to. And you aren't the only one - there are a LOT of GM Onstar customers that are going to be left high and dry. At 10:49 AM 05/21/07, you wrote: __ Well Here in N/W Indiana any Cell Phone even if not in Service Will work to Call 911 . But I go Fishing in a lot of Places that the handheld Cell will not work So I tried to get My old Analog 3 Watt with the roof Mount ant activated No Way I was told No New Activation for Analog But if I would of kept it active I could. For a little longer ?xml:namespace prefix = o ns = urn:schemas-microsoft-com:office:office / Keep in Mind in a Emergency at the Repeater site 911 Will give that Location at the PD Well I guess so would a Regular Phone Patch I picked up 2 Brand New Motorola Bag Phone 3 Watt at a Ham Fest for $5.00 and put it in My wife's car for Emergency use only. Not activated, If you got someone you don't like you can call the Collect at $6.00 and $2.00 a Min PS I recall in the old days of hams making 911 Calls on Repeater Auto Patch We had to spend more time actually trying to Explain to the Dispatcher why Their CAD System shows us in some other Place Miles away from where We were calling, This would take up Valuable time in trying to give Info on the Real Emergency. Good Luck Don KA9QJG ,_._,___
Re: [Repeater-Builder] Cisci LMR Gateway
Dingotel are a VOIP telephony provider, all traffic goes over their network. This is most unsatisfactory for a 2 way radio system that needs privacy and low latency. The dingotel product is USB driven, who wants a PC on a mountaintop? Im sure this thread has been discussed before... G8PWE Uk - Original Message - From: George Henry To: Repeater-Builder@yahoogroups.com Sent: Saturday, May 19, 2007 5:36 PM Subject: Re: [Repeater-Builder] Cisci LMR Gateway - Original Message - From: Kris Kirby [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Saturday, May 19, 2007 7:05 AM Subject: Re: [Repeater-Builder] Cisci LMR Gateway [snip] DingoTel http://www.dingotel.com/2way/index.asp http://www.amazon.com/DingoTel-2Way-Two-Way-Internet-Bridge/dp/B0007LQQUK $30. -- Kris Kirby, KE4AHR [EMAIL PROTECTED] The illegal we do immediately. The unconstitutional takes a bit longer. -- Henry Kissinger Your tagline is quite appropriate, since the use of the DingoTel 2-way with FRS or GMRS radios, as suggested by their list of compatible radios, is illegal... George, WQGJ413 / KA3HSW
Re: [Repeater-Builder] Cisci LMR Gateway
How about the Sipura sp1000 series? Set one to broadcast and the other to hotline, turn all ringing and line tones off. The codec type is selectable or automatic and you can use your own 2 to 4 wire converter. Also available in your price range... Ian G8PWE - Original Message - From: Nate Duehr To: Repeater-Builder@yahoogroups.com Sent: Friday, May 18, 2007 3:45 AM Subject: Re: [Repeater-Builder] Cisci LMR Gateway It's entirely possible to boot the ios on a cheap computer via a usb stick , add a suitable interface /port card for radio control and you have all the advantages of the radio over ip in very cheap package , now if I can do it so can you guys :) although there are other o/s such as certain 'nix telephone devices that I would consider . I've been hunting for a device like the 2-wire ATA VoIP phone adapters that does one or two ports of 4-wire EM for at least three years now... a little sub $100 box that can have a static IP address stuffed in it, and can provide a point-to-point 4-wire EM over IP would be perfect for radio projects. Cisco and others don't make 'em that small... yet. -- Nate Duehr, WY0X
Re: [Repeater-Builder] Re: Quasi-Simulcast?
Quasi .. that just means virtual. Some manufacturers, in the interests of meaningless product diferentiation, choose words for effect. Looking at the article it seems that the quasi part is a precision offset to each base stations frequency so that a stationary mobile will not stay in a null. All the other simulcast rules must be followed and having personally worked on a tait quasi system the automatic transmitter training routines are cool and fast. Hope this isnt too much hot air... Ian G8PWE - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Friday, May 11, 2007 4:56 PM Subject: [Repeater-Builder] Re: Quasi-Simulcast? The article should not be taken as gospel. In fact at first look it appears have a lot of pontification plus potential smoke mirrors. [paste text] For a voter to be working properly, all of the receivers must sound the same. This includes the audio level, and the overall sound. Not really... might be desired but it's not a must-have. You do not want anyone to be able to say that is the north receiver because it sounds different from the rest. Might be something desired but not always an easy do, nor is it actually a requirement. The initial system lineup requires that all of the receivers be perfectly matched to each other in every parameter. Don't know what planet this guy is from... I guess he's never had multiple brands of remote receivers through combinations of phone lines, microwave and/or radio links. You will need high quality testing equipment to accomplish this. You mean I can't use low quality gear? shucks... There's good reason a hot air alarm probably went off for many of you when reading the article. cheers, skipp While reading this article: _http://mrtmag.com/mobile_voice/radio_big_signals_small/_ (http://mrtmag.com/mobile_voice/radio_big_signals_small/) I came across the term quasi-simulcast. Anybody heard of that term? How does it differ from normal simulcast.
Re: [Repeater-Builder] Philips/Simoco FX5000
OK Sylvain, I tried the spreadsheet in Excel 2000 all ok. Excel 2003 - no frequencies calculated. The results are in .hex format. If you give me your frequency I will make a .BIN file for you. G8PWE Birmingham UK - Original Message - From: Sylvain VALAT (F1UJT) To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 07, 2007 10:32 AM Subject: [Repeater-Builder] Philips/Simoco FX5000 Hi everybody, I'm Sylvain F1UJT from center france. I'm on charge of many VHF and UHF repeaters near Limoges. I got a Philips/Simoco FX5000, and i'm looking for .BIN files to put in 2732 eproms in TX and RX module for usage on VHF 2m band. May someone have theses files or help me ? I found GB3GD website, but i can't use the .XLS example files to generate .BIN ! http://www.qsl.net/gb3gd/FX5000_2.htm http://www.qsl.net/gb3gd/downloads/FX5000.zip Many thanks. 73 QRO Sylvain F1UJT
Re: [Repeater-Builder] help?marconi rc690.
Marconi RC690 is a 25w AM radio. Perhaps thats why your rx audio is so bad,its slope detecting the FM. You could use the radios just talking to each other on an AM only net... Ian G8PWE UK - Original Message - From: vince To: Repeater-Builder@yahoogroups.com Sent: Thursday, March 15, 2007 5:46 PM Subject: [Repeater-Builder] help?marconi rc690. hi can any one help pls i have 6 marconi rc690s vhf.all on 2m. thay all trainsmit on the corrcet freqs and recive,but the audio sounds like muffled,like in the back of the box. u can just make out what people r saying .any one ever converted one b4?from what i know, this is all u need to do is to change 1 epprom, witch was done on 2m. i was told no ajustment was req? any help pls i am stuck i have been doing this for over a year,this is all i need to get them all working.thanks vince 73s
Re: [Repeater-Builder] Remote control via text message
This sounds perfect for a backup control system. However, using mobile phone/gsm to control primary systems has the following problems. 1) Latency - texts can sometimes be late.I have known a delay of 24 hours during Christmas and new year peaks. 2) Spam texts - the phones inbox fill with offers for ringtones etc 3) Card top-ups. The procedure and validity of the top up card is controlled by the operator i.e. processes change without notification to the user... you go past the re-activation date and bingo..the only way forward is to get a new card and number. Having stated the above, it can be made to work -Regional Electricity Companies(REC) use Vodaphone to switch pole mounted 11kv vacuum interrupters. Personally at a repeater site I would use a contract phone on low band (900Mhz) with a good external antenna and a proven GSM controller. Matt- Thank you for publicising this article, most interesting. I will of course, be switching my soldering iron on and ordering the PCB/components following the next issue. Ian G8PWE Walsall UK - Original Message - From: Matt Beasant [EMAIL PROTECTED] To: [EMAIL PROTECTED]; Repeater-Builder@yahoogroups.com Sent: Friday, March 02, 2007 9:00 PM Subject: [Repeater-Builder] Remote control via text message Hi This months edition of Everyday Practical Electronics magazine features part one of a project to build a device to enable remote control and remote status indication all via an old Nokia mobile phone suing GSM based SMS service ( text message ) See the magazine web site here: http://www.epemag.wimborne.co.uk/index.html This could sure be useful on remote repeater sites especially ones using battery power or wind/solar power. The design includes battery management functions so as not to overcharge the battery and in the event of a power outage and the phone switching off due to low battery, upon restoration of power, the design switches the phone back on again. Part two will be in the shops next week but copies should be available via the web site's online shop. Matt G4RKY. Note, I have no connection with any of the parties involved in this project in any way. ___ To help you stay safe and secure online, we've developed the all new Yahoo! Security Centre. http://uk.security.yahoo.com Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * 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: 6M duplexer wanted in UK
Dave, Having looked at the GB3FH website,this duplexer looks to be self compensating. Any expansion due to heating of the heliax inner should be compensated by expansion of the linking feeder inner,pushing the tuning bar upwards. I have doubts as to the small effect on tuning that 0.2mm expansion on a 1.3m stub would have (0-40 degC) I also have doubts that an inner constrained and corrugated in foam would self expand in the first place. I think this design could be ideal given some RD time and a little patience..I have my eyes on a 25m piece of 1 5/8 at the moment in the Oxford area.. I just need to persuade the owners that I am not a scrap metal capitalist and need the stuff for a genuine non-profit purpose.. will keep you posted Ian G8PWE Walsall UK - Original Message - From: dave_g7uzn To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 14, 2006 3:37 PM Subject: [Repeater-Builder] Re: 6M duplexer wanted in UK Are you saying that a duplexer built from heliax can cope with a 0.5MHz plit at any temperature?I somehow doubt it (no invar!) Cheers Dave UZN --- In Repeater-Builder@yahoogroups.com, Matt Beasant [EMAIL PROTECTED] wrote: Hi Steve, The 'FH duplexer was built by a very good friend, who doesn't want to build another one!!! But yes, it was built from LDF7-50 1 -5/8 Heliax. Matt - Original Message - From: Steve To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 06, 2006 5:14 PM Subject: Re: [Repeater-Builder] 6M duplexer wanted in UK Hi Matt What size heliax did you use, I seem to remember that it was built for you, wasn't it. I tried myself with small dia stuff and it was not very good, went slightly off tune and of course rx desense. As I have said, itmay just have been the cable I used. 73 Steve - Original Message - From: Matt Beasant To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 06, 2006 4:06 PM Subject: Re: [Repeater-Builder] 6M duplexer wanted in UK My heliax duplexer has been in service now for over 2 years at GB3FH without fault or need to re-adjust. I check it every time I visit site and it never moves! Over 85dB rejection on one side and 90 odd dB on the other, works fine for me. You can see pictures of it at www.gb3fh.org.uk Regards, Matt, G4RKY --- Steve [EMAIL PROTECTED] wrote: Hi don't get me wrong, Iam not condeming heliax duplexers totaly, but you have to take into account reliability once on site. I did make one but had to scrap it as it was so unreliable causing de sense etc, and every time I had to look at it I had to make arragements to access the site, which could take upto 2 weeks, must point out the one I made used small dia heliax, maybe larger dia would be OK but as I can't get any, I don't know Anyway had my say so end of thread from me Steve - Original Message - From: Barry C' To: Repeater-Builder@yahoogroups.com Sent: Wednesday, December 06, 2006 11:25 AM Subject: Re: [Repeater-Builder] 6M duplexer wanted in UK Being a fan to the exclusion of saving several hundred quid is rather silly when the duplexers work well and are generally quite efficient . From: Steve [EMAIL PROTECTED] Reply-To: Repeater-Builder@yahoogroups.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] 6M duplexer wanted in UK Date: Wed, 6 Dec 2006 11:07:54 - Hi think you will find that Dave, like me, isn't a huge fan of Heliax duplexers, see my posts about actualy getting hold of ldf 750 73 Steve - Original Message - From: Mr John Lloyd To: [EMAIL PROTECTED] ; repeater-builder@yahoogroups.com ; John Lloyd Sent: Wednesday, December 06, 2006 6:56 AM Subject: [Repeater-Builder] 6M duplexer wanted in UK Dave, You can build your own 6 Mtr duplexer. Find some 1-5/8 heliax and put one together. Look at http://www.wa7x.com/ki7dx_rpt.html Thanks, John, K7JL Utah VHF Society http://utahvhfs.org/snowlink.html 1a. 6M duplexer wanted in UK Posted by: dave_g7uzn [EMAIL PROTECTED] dave_g7uzn Date: Tue Dec 5, 2006 3:20 am ((PST)) Hi All, Is anyone with a set of cavity filters suitable for 50/51MHz brave enough to sell them to me and get them shipped to the UK for a 6M repeater project? ALL expences will of course be covered. If you can help please email me direct at [EMAIL PROTECTED] __ Need a quick answer? Get one in minutes
Re: [Repeater-Builder] wind up tower noise
Thank you Bob,Trev,Nate,Gary and VA7AA. All of your comments have been most helpful To summarise: Decouple the antenna from the tower Improve feeder bonding Use conductive grease on sliding sections. Ian G8PWE Central England www.gb3dx.net 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: wind up tower noise
Er,Sorry Skip, I cant find a post from you on wind up tower noise Are you thinking of the white noise on 2m.. thread.. Ian - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, May 26, 2006 11:57 PM Subject: [Repeater-Builder] Re: wind up tower noise Re: wind up tower noise Seems like a lot of work before you make some of the baisc checks I mentioned in my post. You can do my list of things to try in less than 1/2 hour without climbing the tower and they will provide serious clues. The below stuff is good to do anyway, but they are not easy first steps to help find the actual problem. cheers, skipp IM Ashford [EMAIL PROTECTED] wrote: All of your comments have been most helpful To summarise: Decouple the antenna from the tower Improve feeder bonding Use conductive grease on sliding sections. 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/
[Repeater-Builder] wind up tower noise
Has anyone experience with eliminating noise fom the metalwork of a wind up tower? Our tower has 4 sections and is of the type where all sections raise at once with a single cable pulley system. The Machine is a Nokia BRS150 using a Sinclair Duplexer on 145.7625/1625 Antenna is Jaybeam Folded Dipole with its own RG214 tail into 60 ft of LDF450. When you shake the trailer mounted tower there is severe crackling on weak signals. The three stays have been tightened up as far as possible. Any Ideas on how to kill this noise guys? Ian Ashford G8PWE Central England UK 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/
[Repeater-Builder] MFJ 1516 repeater antenna
Anybody using the MFJ 1516 repeater antenna ? http://www.mfjenterprises.com/products.php?prodid=MFJ-1516 How long do they last on a non-hilltop environment ? Would you use one on a commercial tower? Any comments gratefully recieved - good or bad Ian G8PWE www.gb3dx.com 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/
