Re: [Repeater-Builder] Re: [OT] Urgent request - probably off-topic but please read...
Where is our moderatoer -- can't we stop this thread -- ??? How did he get here anyway ??? Rick On Thu, Feb 26, 2009 at 10:48 PM, Thomas Oliver tsoli...@tir.com wrote: We do not live in a free country anymore do we? tom [Original Message] From: Nate Duehr n...@natetech.com nate%40natetech.com To: Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com Cc: st...@airspeedonline.com steve%40airspeedonline.com Date: 2/27/2009 1:06:07 AM Subject: [Repeater-Builder] Re: [OT] Urgent request - probably off-topic but please read... Folks, I am not a spammer by trade or by choice in normal circumstances, but I BEG of you to please read this. If you are even a SMALL enthusiast of Aviation, Aerospace or anything related to breaking the surly bonds of earth and reaching skyward, PLEASE take a moment, I beg of you. To my friends and members of: Boulder, CO Linux Users Group Colorado Linux Users and Enthusiasts Rocky Mountain VHF+ Amateur Radio Group Colorado D-STAR Association Grand Mesa Contesters of Colorado Amateur Radio Satellite Corporation and Mailing List Repeater-Builder Mailing List MIT PIC Microcontroller Mailing List Yaesu FT-857 Mailing List VHF Contesting Remailer Mailing List The Internet Radio Radio Linking Project The D-STAR Digital List And other friends and acquaintances who will receive this message privately... and anyone you care to forward it to... Tonight on my way home I fired up my iPod to listen to a podcast by well-known and very well-spoken Steven Force Tupper, an aviation enthusiast from Michigan. What I heard chilled my heart to the bone. The TSA under the auspices of Homeland Security has floated a proposal to restrict and in my opinion, DESTROY numerous legendary aircraft, by limiting their use so heavily that you will never see them in the skies over America again. While this may sound alarmist, please trust me, it's not. You all know me, and know that I can write well, expressing my concerns with politics, living, and even the banal things of life in words, fairly well -- but I can not possibly top the writing of Mr. Tupper. Even more eloquent is his VOICE in his podcast, where he perfectly expresses the frustration, and sheer TERROR that the TSA itself has brought down on the United State's Aviation community with the proposal they've recently released, inappropriately entitled, the Large Aircraft Security Program, or LASP. For the best and most intelligent commentary I've heard on the topic to date -- PLEASE ... LISTEN to his podcast at: http://media.libsyn.com/media/airspeed/AirspeedLASP.mp3 You really must just hear... his voice. I do hope his server can handle an onslaught -- if it can't, wait, and listen later. (I fully intend to help him with the costs associated with distributing his podcast if he needs it this month, it's just that important. Steve, please let me know if you need assistance. I have worked in data centers and web-based businesses, and I understand that publishing these things online to large numbers of people, is NOT free.) It's just over 30 minutes in length, and he NEEDS YOUR SUPPORT -- even if you are NOT a pilot. He gives instructions in the podcast. If you honestly do NOT have time to listen, at least READ and RESPOND to his letter in response to the TSA's Notice of Proposed Rulemaking. He needs your input by TOMORROW. The entire text of his podcast is also available at the link below, if you read faster than you listen -- so to speak. http://airspeedonline.blogspot.com/2009/02/large-aircraft-security-program- capt.html If this non-legislative rule change comes to pass, you and your family may never SEE many historical aircraft or have an opportunity to purchase a RIDE in any classic warbird aircraft in the skies over America ever again. The rule is BROAD and affects modern aircraft also, but the aircraft we will miss the most, are the ones of our history that tell our story as a country. To NOT take action and RESPOND means that you've let a small group of tireless aviation historians, restoration specialists, mechanics, pilots, and everyone who's ever watched an airshow with aircraft from the classic Warbird fleet down. WE NEED YOUR SUPPORT. PLEASE read or listen. Mr. Tupper explains it far better than I possibly can. The TSA's proposal adds NO security to our nation whatsoever. It's simply government run amok. Here's a list from Mr. Tupper's website, of aircraft that I personally believe you will RARELY see in the skies of America again, if the TSA's LASP passes into being without even so much as a single legislator overseeing it, and little to no due-process available to anyone who violates it. Aircraft and Max Takeoff Weight (Varies within Type) Boeing B-17 Flying Fortress - 65,500 Chance Vought F4U Corsair - 14,449
Re: [Repeater-Builder] Got some noise from a fan in the system
Good Morning Peter -- Before I can suggest anything I need some more information. Is this a Motorola repeater, in a cabinet with a motorola power supply? Are you using a motorola RIC, basically - what is the configuration of the repeater? I ask this because it has been well documented in the past that some controllers exhibit fan noise when they are connected in such a way as to control the fan activity or ar in parallel with the power of the repeater on a less than high quality supply capable of handling the repeater total current -- Rick NU7Z On Thu, Feb 19, 2009 at 8:02 PM, Dakota Summerhawk commcon...@gmail.comwrote: Morning, I have a couple of M-10 radios run together with a 12VDC fan keeping them cool in the cabinet. However the power block has them all run into the same line fed by the power supply. You can hear the noise of the fan when you key the repeater. Would a filter help this on the positive line of the fan? Or maybe a coil to filter the noise? I am at a loss as to what might keep the system cool but also eliminate the noise of the fan as well. Thanks for the help in advance. Peter Summerhawk
Re: [Repeater-Builder] Cable velocity
hi there -- Your making this all to hard -- if the coax is teflon then it is most likely .78 or .89 and if it isn't then it is .66. All of the velocity factors are in the ARRL antenna handbook. All you really need is information about the material in the coax and it will be easy to do. whether the center is foam, teflon, or plastic. take the velocity factor for it and built a 2 port harness. put 50 ohm resistors on the ports and measure the input SWR. If it is low, then measure the power into the harness and measure the power at one port. It shouldbe ~3db down. then your good to go. If it looks funny then meaure up and down a Meg and see if it gets any better. Assuming it does then your harness is long or short for the frequency you want to make it for. But most of the time you will be will within the necessary length if you get the correct factor. No matter who made it. GL -- Rick On Mon, Feb 16, 2009 at 7:27 PM, Ralph Hogan rhog...@comcast.net wrote: If you have access to an MFJ antenna anal like the 259 series, in the manual it shows you how to determine the VF with it given a known length of cable to test. Don't know how accurate the measurement will be, but should get you close. Ralph W4XE -Original Message- From: Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com] On Behalf Of mike Sent: Monday, February 16, 2009 8:17 AM To: Repeater-Builder@yahoogroups.com Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] Cable velocity I have been searching for the velocity factor for E86650 cable. This was the stamp on the cable. I think it is simular to RG-59 but want to make sure. I need to build a phasing harness and wanted to use this cable and of course the velocity factor is an important in determining the length. Thanks for any help Mike Yahoo! Groups Links
Re: [Repeater-Builder] Re: Hamtronics Helical Resonator Preamp or Advanced Research Preamp
Hi All -- Here is my take on the preamp vs no preamp situation -- and with Vertex repeaters -- First -- Preamps are not the solution to most of our troubles, in fact it has been my experience over the years that they are more trouble than they are helpful I agree with Skipp and others when it is said to get rid of the LMR-400 and replace it. For inside the box use 142b or 223, something with low loss but is manageable to use on the duplexer and interconnects. rg-214 is way over the top for most of this stuff. For antennas, don't use less than 1/2 heliax. Even '214 will get noisy if there is any flex or it is out in the weather a couple of seasons. No-Preamps, we as amateurs look a preamps as a panacia for many things, including the lack of perceived receiver sensitivity. But it is interesting to note a couple of things. One, a 0.4 uv receiver is as good as it is going to get, in most cases because of the fact your setting in a high place and the MDS combined with the power out, 50 to 75 watts, is going to be about equal with a 4 pole antenna. Not rocket science, and you can actually run that test iif your on a hill and have the proper equipment to do so. Secondly, preamps, even at 10 db gain, really only add about 3 db of signal and the rest is just moving the noise floor higher. And in some cases really create a need for more signal to open the repeaters receiver. If your having issues with the reciever, it would be my recommendation to set down and take a hard look at the equipment, duplexer, antenna, and cables. There are so many variables here in just those 4 items that it will take sometime to optimize each of them to your needs. Coax, again I agree with all of those on here that LMR, 214, 213, RG-8 etc on a repeater is just not a good idea. Use hardline - Vertex, I have nothing bad to say abobut them other than my experience with 2 UHF machines. Both of them exhibit the same characterisitcs so I will just speak in general terms. What I found was that there was/is a lot of crosstalk in the repeater box itself and even though the duplexer was well tuned we could not get the isolation down on the system as a whole. The second problem I found was that the LO runs all the time! This not good it interferes with others on the site and can cause strange mixes within the box that could desense your receiver, especially if there is a signal within the IF of the repeater, either high or low. How did we fix it? We went to a GE box, LOL! So, I guess in conclusion here, before spending your hard earned dollars, for preamps, helical resonators, and the like take good gander at the situation and try to break it down to a common denominator, with a clear picture as to what your seeing. Do all of the things necessary for good repeater operation and then look again. I'll bet you just haven't found the right place to look yet. rick NU7Z On Thu, Feb 5, 2009 at 10:18 AM, skipp025 skipp...@yahoo.com wrote: Hi Ralph, Ralph w7...@... wrote: I have never seen or used a Hamtronics preamp. I don't know anything about their specs or how truthful they are. Maybe some one out there in the great bits might have an answer. Skipp? Eric? anyone?? I'll answer up to the anyone label... Through the years Hamtronics has offered up a number of quite different RF Preamplifier kits and assembled boards. Relative to the industry they are truthful and their products are a good dollar value. Even more valuable is the experience and knowledge many people receive for constructing and setting up their kits. The RF Preamplifier you're probably talking about is not a true helical filter design. Hamtronics no longer offers the HRA series with the on board Toko (brand) helical filter. Their current products (when I last looked) were broad-band and some with modest tuned circuits, which is not really a true helical layout. After completing a recent very large vhf receiver site distribution project... I'm now not so keen on using and depending on or trusting the classic (Toko) type Helical filter assemblies in front receiver pre-amplifiers at locations with strong adjacent signals. The shining star in this most recent project was the now famous GLB pre-amplifier. Please don't confuse my description of the small Toko helical filter assemblies with the helical filters built into many receiver front end circuits/layouts. However, both the performance of your receiver can be and is often directly related to both... but you often can't easily change the receiver (as-built) front end assembly. You get what you get built into the receiver as supplied by the manufacturer. After reading your posts and all the answers... I can write is how I personally would want to know more about the Vertex radio receiver front-end layout before I started making changes. Directly dependent on the receiver front- end layout and performance... would say a lot about what you can successfully park in front of it (the
Re: [Repeater-Builder] Re: Hamtronics Helical Resonator Preamp orAdvanced Research Preamp
Hi Eric and the Group -- Thanks for your comments and yes, Rg-400u is a good substitute as well. I completely forgot about that one -- old age I guess LOL! 73 - Rick NU7Z On Thu, Feb 5, 2009 at 11:05 AM, Eric Lemmon wb6...@verizon.net wrote: Rick, You made some very good points. I can offer two comments: For hookups within the repeater cabinet, use RG-400/U coax instead of RG-142/U. RG-400 has a stranded center conductor, while RG-142 has a solid steel center conductor that breaks easily when repeatedly flexed. Regarding the Vertex UHF repeaters, I corrected an in-cabinet desense problem by replacing all three internal jumpers- which were unmarked gray-jacketed single-shield cables- with double-shielded RG-400 cable. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com] On Behalf Of Rick Beatty Sent: Thursday, February 05, 2009 10:46 AM To: Repeater-Builder@yahoogroups.com Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] Re: Hamtronics Helical Resonator Preamp or Advanced Research Preamp Hi All -- Here is my take on the preamp vs no preamp situation -- and with Vertex repeaters -- First -- Preamps are not the solution to most of our troubles, in fact it has been my experience over the years that they are more trouble than they are helpful I agree with Skipp and others when it is said to get rid of the LMR-400 and replace it. For inside the box use 142b or 223, something with low loss but is manageable to use on the duplexer and interconnects. rg-214 is way over the top for most of this stuff. For antennas, don't use less than 1/2 heliax. Even '214 will get noisy if there is any flex or it is out in the weather a couple of seasons. No-Preamps, we as amateurs look a preamps as a panacea for many things, including the lack of perceived receiver sensitivity. But it is interesting to note a couple of things. One, a 0.4 uV receiver is as good as it is going to get, in most cases because of the fact you're setting in a high place and the MDS combined with the power out, 50 to 75 watts, is going to be about equal with a 4 pole antenna. Not rocket science, and you can actually run that test iif you're on a hill and have the proper equipment to do so. Secondly, preamps, even at 10 dB gain, really only add about 3 dB of signal and the rest is just moving the noise floor higher. And in some cases really create a need for more signal to open the repeater's receiver. If you're having issues with the receiver, it would be my recommendation to sit down and take a hard look at the equipment, duplexer, antenna, and cables. There are so many variables here in just those 4 items that it will take some time to optimize each of them to your needs. Coax, again I agree with all of those on here that LMR, 214, 213, RG-8 etc on a repeater is just not a good idea. Use hardline - Vertex, I have nothing bad to say about them other than my experience with 2 UHF machines. Both of them exhibit the same characteristics so I will just speak in general terms. What I found was that there was/is a lot of crosstalk in the repeater box itself and even though the duplexer was well tuned we could not get the isolation down on the system as a whole. The second problem I found was that the LO runs all the time! This not good; it interferes with others on the site and can cause strange mixes within the box that could desense your receiver, especially if there is a signal within the IF of the repeater, either high or low. How did we fix it? We went to a GE box, LOL! So, I guess in conclusion here, before spending your hard earned dollars, for preamps, helical resonators, and the like take good gander at the situation and try to break it down to a common denominator, with a clear picture as to what you're seeing. Do all of the things necessary for good repeater operation and then look again. I'll bet you just haven't found the right place to look yet. rick NU7Z On Thu, Feb 5, 2009 at 10:18 AM, skipp025 skipp...@yahoo.comskipp025%40yahoo.com mailto:skipp...@yahoo.com skipp025%40yahoo.com wrote: Hi Ralph, Ralph w7...@... wrote: I have never seen or used a Hamtronics preamp. I don't know anything about their specs or how truthful they are. Maybe some one out there in the great bits might have an answer. Skipp? Eric? anyone?? I'll answer up to the anyone label... Through the years Hamtronics has offered up a number of quite different RF Preamplifier kits and assembled boards. Relative to the industry they are truthful and their products are a good dollar value. Even more valuable is the experience and knowledge many people receive for constructing and setting up their kits. The RF Preamplifier you're probably talking about is not a true helical filter design. Hamtronics
Re: [Repeater-Builder] Re: Coax Interconnect (Inside Repeater)
Hi Chuck and the group -- Thanks for this input -- It has been well known for years that the cheapy connectors that most hams purchase won't cut it on repeaters. There are only a couple of manufacturers that I will purchase or that we will purchase in the shop. AMPHENOL silver plated/teflon being one type. As the BNC connectors, well there is many schools of thought about this but good connectors work fine. Heck TX/RX uses them all the time without issue on their duplexers. I also question why we keep hammering on UHF when, we use good connectors, they are still getting a bad rap? UHF has strength and as long as they are treated well they serve well. Where N connectors shine is in wet environments, and where constant impedance is a must. As to coax, RG-8 (214, 213) is not a requirement, use teflon RG-142B or RG-223! Both are very good candidates for repeater and duplexer use. Constant impedance, low loss, good/excellent shield - less leakage (or crosstalk), and easy to work with. Certainly, a plus. Thanks group -- for letting me comment -- Rick NU7Z On Wed, Jan 21, 2009 at 9:21 AM, Chuck Kelsey wb2...@roadrunner.com wrote: You want to steer away from junk connectors, and there are a lot of them out there. BNC's get used with excellent results on all kinds of commercial applications. Use quality, name-brand connectors. Hamfest specials are usually cheap overseas junk. Chuck WB2EDV - Original Message - From: Alexander N Tubonjic kg4...@yahoo.com kg4ogn%40yahoo.com To: Repeater-Builder@yahoogroups.com Repeater-Builder%40yahoogroups.com Sent: Wednesday, January 21, 2009 12:15 PM Subject: [Repeater-Builder] Re: Coax Interconnect (Inside Repeater) Mainly because the BNC connectors seem flimsy in my opinion (I've had two break on two separate HT's over the past few years) and from reading up whats posted on the net everyone seems to agree that steering clear of PL-259 and BNC connectors in repeaters is a good idea.
Re: [Repeater-Builder] RE: What Have I got and can I get information about it.
Hi Eric --and the group -- I will address the amplifier first -- All I need is the schematic -- as the keying relay is inop and I need to get the circuit correct to make it whole again -- LOL! So, if you could help with that it would be great -- I have the amp working, etc -- just need to fix the keying As for the Systel -- Here are the numbers I have -- The unit is a L1574A Tx NUE6862A SP03 Rx NUE6842A I need power supply and crystal data at the very least but a manual or copy of the alignment would be helpful -- Thanks in advance -- Rick NU7Z On Thu, Dec 18, 2008 at 9:46 AM, Eric Lemmon wb6...@verizon.net wrote: Rick, Without model numbers, it is difficult to know what you have. However, I can help with the N1275A power amplifier. It was intended to be used with the N1248A Converta-Com console, and it increased the RF power of the handheld radio from 4.0 watts to 35 watts. You probably have the NLE8912A version- the most common- which is designed to operate in the 450-470 MHz band. The N1275A manual is still available from Motorola Parts. It is part number 6881020C85, and costs about $15. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.comRepeater-Builder%40yahoogroups.com] On Behalf Of Rick Beatty Sent: Wednesday, December 17, 2008 9:37 PM To: Repeater-Builder@yahoogroups.com Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] RE: What Have I got and can I get information about it. I recently was given a SYSTEL unit made by Motorola, on 464.../469... with duplexer and looks to be a repeater, with low level output (2w or so). Would be great for remote work on GMRS, does anyone on the group have data/information on this little cutie? Also I am looking for a schematic for an amplifier used with the portable. a UHF with the number N1275a? thanks in advance -- Rick
Re: [Repeater-Builder] VXR 7000 with desense
Hi Rick -- I am new to the group so I have not seen all of the posts with regards to your problem on the 7000. However, one thing that you may want to check is whether the PL is feeding back into the RX from the TX, if the tones are the same. I have seen this several times in the past on different machines and it is always annoying. Don't assume that just because you can run PL in and out that it will be able to run the same tone. GL -- Rick NU7Z On Thu, Dec 18, 2008 at 9:44 AM, Doug Bade k...@thebades.net wrote: Rick; I think you need to isolate whether it is tx through the duplexer or something else bothering the rx and or squelch. It sounds like the tx signal fundamentally is clean from your analysis so far.. in order to isolate through the duplexer, connect the tx directly to a dummy load instead of it's side of the duplexer while injecting rx into the duplexer. if it does not cycle, the tx is sending something through the duplexer to the rxif it does cycle.. it is an internal issue as you suspect.. I would use the tx to duplexer cable in the dummy load path as you want to see if some radiation from it is part of the equation. I lean more to spurious on initial keyup... causing a noise burst maybe due to exciter tuning... but this test should tell you if it is conducted internally or passed through the duplexer. Doug KD8B At 05:04 PM 12/17/2008, you wrote: Hi, I've checked the previous posts on this issue, but I am hoping that there is more light to be shed. We have a VXR 7000 that has had issues for a while as a two meter repeater. In the shop we set it up with its DB 4026 duplexer and 50 ohm dummy load and monitored the output power with a Bird thru line watt meter. We used a service monitor to inject the RX signal to get 10 dB quieting (approx 0.2 micro volt). Put the unit into repeat mode and the repeater will cycle (go in and out of transmit) until the RX signal is increased about 20 to 25 dB (approx 3.6 micro volt). Looking at what is coming in the receive port with the transmitter is keyed is about -75 dBw (50 watt out with about 95 dB of isolation) at the TX frequency, and there is little to no hash at the RX frequency - seeing the noise floor of the spectrum analyzer (-120 dB). Put the 7000 into base station mode, hooked up second signal source, set first signal source to give 10 dB quieting at the RX frequency (0.2 uV), set the second signal source to emulate what we saw from the duplexer (79 mV at TX frequency) and there was no desense. Increased the simulated TX voltage to better than 1 volt and still no desense. My thought is that something has gone bad internally within the 7000. Is there something else I need to try? Thanks in advance for your help. Regards, Rick, N5RB
Re: [Repeater-Builder] RC96 manual
John -- et al -- I opened the zip without issue and everything is there as far as I can tell -- send me an email and I will send the 160 pages to you -- LOL! Rick On Thu, Dec 18, 2008 at 2:43 PM, Joe k1ike_m...@snet.net wrote: Kevin sent this link and it works. http://www.repeater-builder.com/acc/acc-rc-96-manual.zip 73, Joe, K1ike John Transue wrote: Joe, I get the same message when trying to download the file. I have a hard copy but no electronic copy. Let me know if you want me to copy it for you. John Transue
Re: [Repeater-Builder] DATARADIO 96+ Manual needed
Kenny, I sent you a copy of the manual -- unzipped -- Rick NU7Z On Thu, Dec 18, 2008 at 2:56 PM, KG5KS - Kenny Thompson kg...@yahoo.comwrote: Guess the ham that said he would send the manual has forgotten about it..hi I need a manual with pinout or specs for the Dataradio 96+ unit. I'm wanting to see if they could be used in a ham radio application. I have not found out anything online that would show me what pinouts and specs. I appreciate it! Thank you 73 Kenny ARS KG5KS Currently DEC B, EC Jackson County, OBS, ORS, ARRL VE Courses completed Nims 700, ICS 100, 200, 300, 400, 702, 317, 394, 240, 242, 139, 245, 275, 230, 235, 800, ARECC 1, Skywarn Certified Continuously, Past Public Safety Officer for State.
[Repeater-Builder] RE: What Have I got and can I get information about it.
I recently was given a SYSTEL unit made by Motorola, on 464.../469... with duplexer and looks to be a repeater, with low level output (2w or so). Would be great for remote work on GMRS, does anyone on the group have data/information on this little cutie? Also I am looking for a schematic for an amplifier used with the portable. a UHF with the number N1275a? thanks in advance -- Rick
