Re: [Repeater-Builder] LOOONG audio runs
I have to stick my nose into this one. Use balanced audio ESPECIALLY if there is any other strong RF at or near your site. 140 feet is a good AM broadcast antenna! Shield grounds for your cable should be at one end (best bet is at the controller for everything!) It also might be wise to snap on an RF choke at each end of the cable, after all ... you don't need any strong RF on your analog signaling lines to get rectified somewheres and present you with a locked up or in-operable repeater. my 0.02 James WJ1D JOHN MACKEY wrote: I have a odd situation where I need to run long audio cables between my repeater controller and two repeaters. In this case, the repeater controller will be connected to 2 repeaters in the same cabinette. The other two repeaters will connected thru about 140 feet of wiring to the other side of a building. I am thinking of using balanced audio wires for the long runs and using Henry Engineeering boxes to convert between balanced/un-balanced at each end. Anyone ever done long audio runs like this? Am I over engineering it and unbalanced will be good enough? I use the Henry Engineering boxes for several audio conversions in broadcasting, here is a link for what they are:
RE: [Repeater-Builder] LOOONG audio runs
John, The professional sound and recording industry addressed this problem long ago, when wired microphones and other pickups needed to be run several hundred feet from the performer on stage to the mixing board. We used balanced twisted pair shielded cable with XLR connectors on each end. A device called a Direct Box is used to convert unbalanced to balanced, and also avoid ground-loop issues. Since it is important to have a high-quality transformer in a direct box, I made my own with units from Jensen Transformer- a company that is still in business today. http://www.jensen-transformers.com/ 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of JOHN MACKEY Sent: Friday, February 26, 2010 10:49 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] LOOONG audio runs I have a odd situation where I need to run long audio cables between my repeater controller and two repeaters. In this case, the repeater controller will be connected to 2 repeaters in the same cabinette. The other two repeaters will connected thru about 140 feet of wiring to the other side of a building. I am thinking of using balanced audio wires for the long runs and using Henry Engineeering boxes to convert between balanced/un-balanced at each end. Anyone ever done long audio runs like this? Am I over engineering it and unbalanced will be good enough? I use the Henry Engineering boxes for several audio conversions in broadcasting, here is a link for what they are: http://www.henryeng.com/matchbox.html http://www.henryeng.com/matchbox.html
[Repeater-Builder] Re: Looking for Preamp info
Just had one on the bench last night, about 3 db hotter than anything else. I have no info, was told by the guy I got it from that tehre is a GaAsFET in there. I had this on a Mastr repeater, one cavity ahead of it, it ahead of duplexer, and at 50 watts into PD526 has zip desense. GeorgeC W2DB --- In Repeater-Builder@yahoogroups.com, w9srv tgundo2...@... wrote: Picked up a UHF Micor repeater yesterday, Attached to it was a Lunar PAG463 preamp. Anybody have any recollection of these or info on them? Google has come up dry. Thanks! Tom W9SRV
RE: [Repeater-Builder] Re: Micor UHF Repeater Base 9.6 vdc current requirement?
In a station, the 9.6 volt circuitry *could* be run from 12 volts, as long as its regulated. I'm not suggesting someone does that, because the circuits were optimized for 9.6 volts, but I'm trying to make a point. Point taken, but to add to your cautionary note, there are some circuits that will not be happy at 12V. I remember trying to run a Micor PL decoder off 13V and it did some strange things (i.e. didn't work right/reliabily). If it were me, I'd just use a 9 or 10 volt three terminal regulator (7809 or 7810) and skip the whole LM-317 or diodes in the ground leg deal. It only serves to make the circuitry more involved , harder to mount, and for NO advantage whatsoever. In general I don't like raising the ground on 7xxx series fixed regulators by adding diodes to what would normally be the ground lead. 7xxx series regulators can (and will) oscillate, which is why adding caps per the datasheets' recommendations isn't just a good idea, it's mandatory. My concern is that putting a diode in series with the ground lead results in the filter/bypass caps being at a different ground potential than the device, which may increase the chance of oscillation. --- Jeff WN3A
RE: [Repeater-Builder] LOOONG audio runs
I have a odd situation where I need to run long audio cables between my repeater controller and two repeaters. In this case, the repeater controller will be connected to 2 repeaters in the same cabinette. The other two repeaters will connected thru about 140 feet of wiring to the other side of a building. I am thinking of using balanced audio wires for the long runs and using Henry Engineeering boxes to convert between balanced/un-balanced at each end. I'd definately go balanced, but I'd use transformers rather than active balanced devices. Decent transformers (even audiofile-grade Jensens) would still cost less than Henry matchboxes (or anyone else's active converters most likely), and be more reliable. Back in the old days, Western Electric 111C repeating coils were supplied by the telco for program audio lines. Look around broadcast transmitter sites and old studios, you'll probably find a few nailed up to the telco backboard that the LEC no longer has an interest in maintaining ownership of... The common mode rejection of Henry matchboxes isn't all that great, I've tested them. If you can, keep the audio level high on the sending side (I think 111C's were good up to close to a watt at 600 ohms!), and pad it down on the far side's secondary as necessary to maximize S/N. --- Jeff WN3A
[Repeater-Builder] Suggestions for signal generator?
Anyone have a suggestion for a simple 50 ohm signal generator? I have a number of VHF Phelps Dodge duplexers and several UHF flat pack duplexers I'd like to be able to test prior to sale and possibly rough tune for a few projects duing the waning weeks of winter. I realize a network analyzer would be the best case option for doing this sort of work; followed by possibly a service monitor and a spectrum analyzer with tracking generator. I currently have an HP spectrum analyzer available at work; unfortunately it did not come equiped with a tracking generator. It does have a current calibration; I'm guessing I could use it to determine the exact output from a signal generator and subsequently the insertion loss from the duplexer.
Re: [Repeater-Builder] Digest Number 7130
John, You will save yourself a lot of grief by using real transformer isolation at each end in addition to balanced lines. The $12 dollar ones at RS will work fine for communication audio frequencies. If you want to go first class find some WE111 repeat coils. For wire CAT 5 will work and give you four pairs to play with. Some E and M signaling or COR maybe.? Al, K9SI, retired BC engineer (now occasional highly paid consultant) LOOONG audio runs Posted by: JOHN MACKEY jmac...@usa.net jmackey_usa_net Date: Fri Feb 26, 2010 10:49 pm ((PST)) I have a odd situation where I need to run long audio cables between my repeater controller and two repeaters. In this case, the repeater controller will be connected to 2 repeaters in the same cabinette. The other two repeaters will connected thru about 140 feet of wiring to the other side of a building. I am thinking of using balanced audio wires for the long runs and using Henry Engineeering boxes to convert between balanced/un-balanced at each end. Anyone ever done long audio runs like this? Am I over engineering it and unbalanced will be good enough? I use the Henry Engineering boxes for several audio conversions in broadcasting, here is a link for what they are: http://www.henryeng.com/matchbox.html
[Repeater-Builder] Re: Manual for HAL ID-1000?
Chris - I have 2 of the HAL ID-1A units that I picked up surplus from a Western NY utility company last year. They used these 2 units on their older repeater systems (circa 1970s) -- and one unit -- was converted fro 120 VAC to 12 VDC. YES, they are diode matrix programmed (for ID) -- which was state of the art (user friendly, not requiring programmer or skills) in that era (1970s). The Icom IC-22S was a 2-meter radio that also used this approach for channel programming! I called Mr. Henry, who is president of HAL (and late 1950s EE grad for University of Illinois) and purchased the manual directly for HAL Communications (great printing) -- about $25 with shipping. Provides the theory of operation, function descriptions for interfacing and matrix grid programming You program the DOT, DASH and SPACE between characters HAL Communicaitons 1201 West Kenyon Road Urbana, IL 61801-1033 Telephone: (217) 367-7373
Re: [Repeater-Builder] Suggestions for signal generator?
On Sat, 27 Feb 2010, AJ wrote: Anyone have a suggestion for a simple 50 ohm signal generator? I have a number of VHF Phelps Dodge duplexers and several UHF flat pack duplexers I'd like to be able to test prior to sale and possibly rough tune for a few projects duing the waning weeks of winter. I realize a network analyzer would be the best case option for doing this sort of work; followed by possibly a service monitor and a spectrum analyzer with tracking generator. I currently have an HP spectrum analyzer available at work; unfortunately it did not come equiped with a tracking generator. It does have a current calibration; I'm guessing I could use it to determine the exact output from a signal generator and subsequently the insertion loss from the duplexer. You'd probably want to drive the VCO of the signal generator directly to make it sweep up, but if you don't have a good baseline on how it's power level varies over the range, you won't be able to compare with the antenna response. Something like an MFJ-259 attached to a sweep generator would probably do the job. Of course, the MFJ-259 doesn't have great frequency stability, but you're not staying in one place for very long. Then you can use the spectrum analyzer for what it does best. -- Kris Kirby, KE4AHR Disinformation Analyst
[Repeater-Builder] Micor Stock Power Supplies
I have been following the 9.6 Volt Micor Voltage information. One post indicated that if one were to replace the Stock MICOR Supply with a switcher and add the 9.6 Volt circuit, the monthly electric bill to run the repeater could be significantly reduced. Is this due to the fact that the switcher, in the standby mode, draws much less current and therefore cost less to operate or is it this combined with efficiently when the repeater is in operation. I have stock MICOR and MASTR II Supplies and would like your expertise on the merits of replacing them with one large switcher or a couple switchers. As always thanks in advance for your input and sharing your experiences with us. 73 JIM KA2AJH Wellsville, N.Y.
RE: [Repeater-Builder] Micor Stock Power Supplies
Jim, I performed load tests on many different power supplies, including the ferroresonant supplies common to Motorola and GE stations. The results are posted in the Power Supplies folder in the Files section of the Repeater-Builder Group. As shown by the efficiency numbers, switchers are far more economical to operate than linear or ferroresonant supplies- especially at the low current draw in standby mode. Indeed, some busy mountaintop repeater sites are heated solely by the waste heat produced by vintage power supplies. If you're paying for power at your repeater site, your clunker power supply is costing you a chunk of change. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of James Sent: Saturday, February 27, 2010 9:56 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor Stock Power Supplies I have been following the 9.6 Volt Micor Voltage information. One post indicated that if one were to replace the Stock MICOR Supply with a switcher and add the 9.6 Volt circuit, the monthly electric bill to run the repeater could be significantly reduced. Is this due to the fact that the switcher, in the standby mode, draws much less current and therefore cost less to operate or is it this combined with efficiently when the repeater is in operation. I have stock MICOR and MASTR II Supplies and would like your expertise on the merits of replacing them with one large switcher or a couple switchers. As always thanks in advance for your input and sharing your experiences with us. 73 JIM KA2AJH Wellsville, N.Y.
Re: [Repeater-Builder] LOOONG audio runs
I vigorously second Jeff's recommendation. This is an application where iron is still the right answer. Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application. Repeat coils are the classic answer. Here's a hint about what you are looking for if you don't already know: http://users.snip.net/~mrbibbs/gearpix/Western_Electric_Repeat_Coils_4040.jpg http://users.snip.net/~mrbibbs/gearpix/Western_Electric_Repeat_Coils_4042.jpg http://oldphoneguy.net/Coils1.jpg Jensen's stuff is really nice, but you'd be paying a premium price for performance you can't use. If you can't find an old set of repeat coils, most small audio transformers with reasonable turns ratios will do the job fine. Reasonable in this case is probably less than 4 or 5:1, though 1:1 would be best. I'm not sure where you are, but if you can't find anything easily, the coupling transformers out of **OLD** modems (1200 Baud or less) are likely suspects. On 2/27/2010 10:32 AM, Jeff DePolo wrote: I'd definately go balanced, but I'd use transformers rather than active balanced devices. Decent transformers (even audiofile-grade Jensens) would still cost less than Henry matchboxes (or anyone else's active converters most likely), and be more reliable. Back in the old days, Western Electric 111C repeating coils were supplied by the telco for program audio lines. Look around broadcast transmitter sites and old studios, you'll probably find a few nailed up to the telco backboard that the LEC no longer has an interest in maintaining ownership of... The common mode rejection of Henry matchboxes isn't all that great, I've tested them. If you can, keep the audio level high on the sending side (I think 111C's were good up to close to a watt at 600 ohms!), and pad it down on the far side's secondary as necessary to maximize S/N. --- Jeff WN3A -- mailto:o...@ozindfw.net Rich Osman N1OZ POB 93167 Southlake, TX 76092 (Near DFW Airport)
Re: [Repeater-Builder] Re: Micor UHF Repeater Base 9.6 vdc current requirement?
Hi Jeff, In general I don't like raising the ground on 7xxx series fixed regulators by adding diodes to what would normally be the ground lead. You're right, the diode trick is not recommended. National recommends putting a voltage divider across the output of the regulator and connecting the ground lead to the tap. See: http://www.national.com/ds/LM/LM340.pdf. 73, Bob, WA9FBO -Original Message- From: Jeff DePolo j...@broadsci.com To: Repeater-Builder@yahoogroups.com Sent: Sat, Feb 27, 2010 9:32 am Subject: RE: [Repeater-Builder] Re: Micor UHF Repeater Base 9.6 vdc current requirement? In a station, the 9.6 volt circuitry *could* be run from 12 volts, as long as its regulated. I'm not suggesting someone does that, because the circuits were optimized for 9.6 volts, but I'm trying to make a point. Point taken, but to add to your cautionary note, there are some circuits that will not be happy at 12V. I remember trying to run a Micor PL decoder off 13V and it did some strange things (i.e. didn't work right/reliabily). If it were me, I'd just use a 9 or 10 volt three terminal regulator (7809 or 7810) and skip the whole LM-317 or diodes in the ground leg deal. It only serves to make the circuitry more involved , harder to mount, and for NO advantage whatsoever. In general I don't like raising the ground on 7xxx series fixed regulators by adding diodes to what would normally be the ground lead. 7xxx series regulators can (and will) oscillate, which is why adding caps per the datasheets' recommendations isn't just a good idea, it's mandatory. My concern is that putting a diode in series with the ground lead results in the filter/bypass caps being at a different ground potential than the device, which may increase the chance of oscillation. --- Jeff WN3A
Re: [Repeater-Builder] LOOONG audio runs
Oz, in DFW wrote: Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application. I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe
[Repeater-Builder] Re: Manual for HAL ID-1000?
I will send those specific pages -- How to program Diode matrix and schematic diagram for the HAL ID-1A to Repeater Builders for posting (access), The FULL manual is still available for HAL Communications, Urbana, IL greg w9gb
[Repeater-Builder] Re: Motorola Power Supply Questiona
Mike, Your comments and help is very much appreciated. You have gone to an effort to help me greatly and I extend my thanks to you. Great details! The TPN number is TPN2264 SP01 It has been mentioned to me that the SP could mean either special product or special price. I haven't actually powered it up yet but will do so shortly and check output voltages. My reason for asking about this supply is that well ... I have it and could sure use it if it proves to be suitable for my application - powering dc devices and a couple of UHF repeaters in my mobile home when plugged into grid power (the charging circuits would be a bonus for keeping the batteries topped up - but as has been mentioned already it would probably not be good for my AGMs.) I got it for next to nothing so saw it as a cost effective solution. My other option is a switch-mode bench supply @ 40amps continuous that I also have. A bit concerned about RFI into radio equipment tho. It is one of the POWERTECH MP3090 models such as this - http://tinyurl.com/y9nl85a The model I have has digital volts and amps meters - so a good way of keeping a tab on current draws. What do list members think of using this supply as an alternative to the Motorola one? I know which is a lot lighter to pick up and move around! Thanks all Graham ZL3TV New Zealand --- In Repeater-Builder@yahoogroups.com, Mike Morris wa6i...@... wrote: The photo looks like a repeater supply. Many repeater supplies provided a 9.6v DC low current output for the receiver and exciter, some had a second low current output at 13.5-13.8vDC at 3-4 amps for the other audio stages, and most had an unregulated (as high as 16v) high current output for the transmitter RF amplifier section. The 16vDC is not suitable for high current loads that expect 12-14 volts. You will cook / boil your batteries. The 25-series number is for the power transformer only. Motorola parts department always formatted their part numbers with a 2-digit prefix to identify the type of part. See http://www.repeater-builder.com/motorola/numerical-parts-categories.html TB602 is a label for a connector that goes to somewhere else in the radio cabinet. It probably has the 9.6 or 12v low current, or ? Some supplies had a battery charger circuit in them. Some had a battery backup section (i.e. an automatic load switchover from the mains supply to the battery bank. Please look for a rubber stamped number somewhere on the chassis that starts with TPN, followed by 4 digits and maybe a suffix with some letters and numbers after it - something like TPN1095A, or TPN1152B1, or something in that format. USUALLY, but not always, there is a letter after the 4 digits, occasionally there is a number after the letter, and rarely there is a number at the end. There is no way to tell exactly what voltages, or features your supply has in it without seeing the actual physical supply, or looking at the manual. If you provide the complete TPN number we can look it up to see what type of station (radio) it came from, then look at the manual for that station. BTW the TPN comes from: T = Two way radio product P = Power supply, or power supply related N = Not frequency sensitive . The last letter usually was structured like this: A Under 25 MHz B 25-54 MHz C 66-88MHz D 144-174 MHz E 390-550 MHz F 890-960 MHz N Not frequency dependent See http://www.repeater-builder.com/motorola/aaa-numbering-scheme.html Mike Morris WA6ILQ
[Repeater-Builder] 900 meg Spectra radio
Ya, I bought the cable from ebay and I had an old laptop. I've walked past this stuff for years at hamfests and heard the horror stories. Motorola did everything they could to make this radio proprietary ..like everything else. I even replaced the display caps and some on the audio. blah blah blah The radio still has the programming from the dump truck it was in. I had even considered building something like a development board for the code plug just so I could get into the proms.The processor has mem in it too . Don't expect the USB programming cable to work by itself . You need the rib box too. tx and rx ok ther has to be a better way like make a new front panel for it . Now I'm looking at a newer mobile hoping I can get into that and change the splits , tone etc. Someone here had a Kenwood 800 meg but the tx and the front end would need rework too . Why cant someone just come up with a 900 meg fm mobile for amateur use? They would sell a zillion of them . Motorola is splitting up and moving out to silicon valley. They are vacating all their facilities in Schaumburg and Illinois.
[Repeater-Builder] Re: New to 900mhz,, PL or DPL?
Then it's not COR [Carrier Operated Relay]. It would be RUS [Receiver UnSquelch]. And running any voice station strictly on PL/DPL is a bad idea. PL [CTCSS] is prone to falsing if it isn't AND'ed with carrier detect. I have to figure that DPL is better, but random energy from the 'hiss' has got to false the decoder once in a while. BTW, my agency uses the same 2 PL tones across the state, whether high RF site or not. And the majority of 440 ham repeaters in my area use the SAME 100.0 Hz tone for access. So, unless you have some desire to restrict who can access your repeater [since some radios WON'T do DPL], then my recommendation is PL. But stay away from 179.9 Hz, as that can be falsed by the third harmonic of the mains. And choose one that's neither at the top nor bottom of the list. WalterH --- In Repeater-Builder@yahoogroups.com, kq7dx kq...@... wrote: Thank you for all the replies and great information. I have another question on code selection. Other than 411 being a code used for open repeater, what is the criteria for picking a DPL code. Also it looks like PL being preferred to DPL is not RFI specific as I have seen on frequency lists with PL being used in high RFI locatations. What do you think about leaving the squelch open and letting the DPL control the COR. Thanks again... The DPL list I found. Standard 83 Digital Coded Squelch Codes 0nn 1nn 2nn 3nn 4nn 5nn 6nn 7nn 023 114 205 306 411 503 606 703 025 115 223 311 412 506 612 712 026 116 226 315 413 516 624 723 031 125 243 331 423 532 627 731 032 131 244 343 431 546 631 732 043 132 245 345 432 565 632 734 047 134 251 351 445 654 743 051 143 261 364 464 662 754 054 152 263 365 465 664 065 155 265 371 466 071 156 271 072 162 073 165 074 172 174
RE: [Repeater-Builder] Re: Motorola Power Supply Questiona
Graham, The SP01 might refer to a power supply that is modified to operate on 230 VAC 50 Hz, or that is fitted with the special Type 1 plug used in New Zealand, or both. In any case, the SP01 does, in fact, mean that the unit is a special product that may have been custom-made for a particular customer, or that it is equipped with a non-standard option. I have no info on a TPN2264 power supply. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of zl3tda Sent: Saturday, February 27, 2010 5:05 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Motorola Power Supply Questiona Mike, Your comments and help is very much appreciated. You have gone to an effort to help me greatly and I extend my thanks to you. Great details! The TPN number is TPN2264 SP01 It has been mentioned to me that the SP could mean either special product or special price. I haven't actually powered it up yet but will do so shortly and check output voltages. My reason for asking about this supply is that well ... I have it and could sure use it if it proves to be suitable for my application - powering dc devices and a couple of UHF repeaters in my mobile home when plugged into grid power (the charging circuits would be a bonus for keeping the batteries topped up - but as has been mentioned already it would probably not be good for my AGMs.) I got it for next to nothing so saw it as a cost effective solution. My other option is a switch-mode bench supply @ 40amps continuous that I also have. A bit concerned about RFI into radio equipment tho. It is one of the POWERTECH MP3090 models such as this - http://tinyurl.com/y9nl85a http://tinyurl.com/y9nl85a The model I have has digital volts and amps meters - so a good way of keeping a tab on current draws. What do list members think of using this supply as an alternative to the Motorola one? I know which is a lot lighter to pick up and move around! Thanks all Graham ZL3TV New Zealand --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Mike Morris wa6i...@... wrote: The photo looks like a repeater supply. Many repeater supplies provided a 9.6v DC low current output for the receiver and exciter, some had a second low current output at 13.5-13.8vDC at 3-4 amps for the other audio stages, and most had an unregulated (as high as 16v) high current output for the transmitter RF amplifier section. The 16vDC is not suitable for high current loads that expect 12-14 volts. You will cook / boil your batteries. The 25-series number is for the power transformer only. Motorola parts department always formatted their part numbers with a 2-digit prefix to identify the type of part. See http://www.repeater-builder.com/motorola/numerical-parts-categories.html http://www.repeater-builder.com/motorola/numerical-parts-categories.html TB602 is a label for a connector that goes to somewhere else in the radio cabinet. It probably has the 9.6 or 12v low current, or ? Some supplies had a battery charger circuit in them. Some had a battery backup section (i.e. an automatic load switchover from the mains supply to the battery bank. Please look for a rubber stamped number somewhere on the chassis that starts with TPN, followed by 4 digits and maybe a suffix with some letters and numbers after it - something like TPN1095A, or TPN1152B1, or something in that format. USUALLY, but not always, there is a letter after the 4 digits, occasionally there is a number after the letter, and rarely there is a number at the end. There is no way to tell exactly what voltages, or features your supply has in it without seeing the actual physical supply, or looking at the manual. If you provide the complete TPN number we can look it up to see what type of station (radio) it came from, then look at the manual for that station. BTW the TPN comes from: T = Two way radio product P = Power supply, or power supply related N = Not frequency sensitive . The last letter usually was structured like this: A Under 25 MHz B 25-54 MHz C 66-88MHz D 144-174 MHz E 390-550 MHz F 890-960 MHz N Not frequency dependent See http://www.repeater-builder.com/motorola/aaa-numbering-scheme.html http://www.repeater-builder.com/motorola/aaa-numbering-scheme.html Mike Morris WA6ILQ
[Repeater-Builder] Re: LOOONG audio runs
Joe k1ike_m...@... wrote: I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe A number of different items in the specifications would be worth examining... like how much C per foot and I don't believe CAT network cables are shielded. s. Oz, in DFW wrote: Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application.
Re: [Repeater-Builder] Re: LOOONG audio runs
Skipp, yes you can get shielded Cat 5. I've used it a few times when running near AC fixtures etc. 73 John VE3AMZ - Original Message - From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Saturday, February 27, 2010 10:43 PM Subject: [Repeater-Builder] Re: LOOONG audio runs Joe k1ike_m...@... wrote: I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe A number of different items in the specifications would be worth examining... like how much C per foot and I don't believe CAT network cables are shielded. s. Oz, in DFW wrote: Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application. Yahoo! Groups Links
Re: [Repeater-Builder] Re: LOOONG audio runs
Skipp- They make Shielded Cat 5 6, as well as shielded RJ45 ends. Takes a special crimp tool but it is available. Also, Belden and other wire manufactuers are making special series of Cat cables with low-skew design specifically for the purposes of sending Audio Video down the Cat cables. We're using baluns all the time for av purposes these days. Can go 1000ft over cat 5 for standard analog audio and baseband video with no significant losses, and we don't use shielded in most cases, never had any interference. Hi-def video formats are shorter distances, passive VGA baluns usually call for shielded cat5 or 6 where as active do not. Tom W9SRV --- On Sat, 2/27/10, skipp025 skipp...@yahoo.com wrote: From: skipp025 skipp...@yahoo.com Subject: [Repeater-Builder] Re: LOOONG audio runs To: Repeater-Builder@yahoogroups.com Date: Saturday, February 27, 2010, 9:43 PM Joe k1ike_m...@... wrote: I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe A number of different items in the specifications would be worth examining... like how much C per foot and I don't believe CAT network cables are shielded. s. Oz, in DFW wrote: Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application. Yahoo! Groups Links
[Repeater-Builder] Re: LOOONG audio runs
Shielding is not usually necessary for line level balanced pair audio on CAT 5 or any good twisted pair. CAT 5 is often used in broadcast audio work. Laryn K8TVZ --- In Repeater-Builder@yahoogroups.com, skipp025 skipp...@... wrote: Joe k1ike_mail@ wrote: I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe A number of different items in the specifications would be worth examining... like how much C per foot and I don't believe CAT network cables are shielded.
Re: [Repeater-Builder] 900 meg Spectra radio
Because 900 Mhz is only available to amateurs in the US and not in Japan. The 900 Mhz amateur activity in the US is not very strong. -- Original Message -- Received: Sat, 27 Feb 2010 07:02:17 PM PST From: Fuggitaboutit mikew...@hotmail.com To: Repeater-Builder@yahoogroups.com SNIP Why cant someone just come up with a 900 meg fm mobile for amateur use? They would sell a zillion of them .
[Repeater-Builder] Files Uploaded
Hello all, I've created 2 folders, and uploaded a few files to them They are DB-224 and DB Antennas. These are for passing along files relating to the Decible DB antennas. If the moderators could move some of the other files that are scattered around the files page, it would make it alot easier to find them Thanks and enjoy!! Steve KD8BIW KD8BIW/R 224.580 N8IHI/R 147.105 W3YXS/R 146.745 KD8JBF/R 444.2625 http://www.kd8biw.com
Re: [Repeater-Builder] Re: LOOONG audio runs
Using balanced audio in a broadcast environment, I have on rare occasions experienced issues with cross-talk between long runs of un-shielded balanced audio lines. (inductive pickup??) I always wondered if the wires were truly balanced when that happened. I prefer to used shielded balanced wiring for long runs. -- Original Message -- Received: Sat, 27 Feb 2010 08:16:55 PM PST From: larynl2 lar...@hotmail.com To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: LOOONG audio runs Shielding is not usually necessary for line level balanced pair audio on CAT 5 or any good twisted pair. CAT 5 is often used in broadcast audio work. Laryn K8TVZ --- In Repeater-Builder@yahoogroups.com, skipp025 skipp...@... wrote: Joe k1ike_mail@ wrote: I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe A number of different items in the specifications would be worth examining... like how much C per foot and I don't believe CAT network cables are shielded.
Re: [Repeater-Builder] Re: LOOONG audio runs
At the multi-FM broadcast transmitter site I work at ALL my network wiring is shielded cat5 or shielded cat6. I have never experienced some of the strange networking problems related to interference that I occasionally hear others complain about. At my studio I had a problem a couple years ago where a server was locking up on the NIC plus a few other problems and it was a 1GB network for the backbone. I replace the UTP-cat5 with shielded cat5 and all the problems went away. -- Original Message -- Received: Sat, 27 Feb 2010 07:55:38 PM PST From: John J. Riddell ve3...@earthlink.net To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: LOOONG audio runs Skipp, yes you can get shielded Cat 5. I've used it a few times when running near AC fixtures etc. 73 John VE3AMZ - Original Message - From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Saturday, February 27, 2010 10:43 PM Subject: [Repeater-Builder] Re: LOOONG audio runs Joe k1ike_m...@... wrote: I wonder if CAT 6 would be better than CAT5 due to the difference in twist? Joe A number of different items in the specifications would be worth examining... like how much C per foot and I don't believe CAT network cables are shielded. s. Oz, in DFW wrote: Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application. Yahoo! Groups Links
Re: [Repeater-Builder] LOOONG audio runs
I think when I made the original post it was late I was tired!! I work in broadcasting and use the 111C coils often in long analog audio runs for remote broadcasts. I do agree that transformers would be better than active balanced devices. The active devices are easier to deal with for short audio runs in a production room or control room when you have to interface with something that is consumer grade un-balanced. But for the long runs I definately agree that 111C coils are the best option. -- Original Message -- Received: Sat, 27 Feb 2010 01:24:49 PM PST From: Oz, in DFW li...@ozindfw.net To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] LOOONG audio runs I vigorously second Jeff's recommendation. This is an application where iron is still the right answer. Make sure you use twisted pair. Station wire like that use to wire houses is often not twisted. Ethernet cable is good and has a high twist pitch - better for this application. Repeat coils are the classic answer. Here's a hint about what you are looking for if you don't already know: http://users.snip.net/~mrbibbs/gearpix/Western_Electric_Repeat_Coils_4040.jpg http://users.snip.net/~mrbibbs/gearpix/Western_Electric_Repeat_Coils_4042.jpg http://oldphoneguy.net/Coils1.jpg Jensen's stuff is really nice, but you'd be paying a premium price for performance you can't use. If you can't find an old set of repeat coils, most small audio transformers with reasonable turns ratios will do the job fine. Reasonable in this case is probably less than 4 or 5:1, though 1:1 would be best. I'm not sure where you are, but if you can't find anything easily, the coupling transformers out of **OLD** modems (1200 Baud or less) are likely suspects. On 2/27/2010 10:32 AM, Jeff DePolo wrote: I'd definately go balanced, but I'd use transformers rather than active balanced devices. Decent transformers (even audiofile-grade Jensens) would still cost less than Henry matchboxes (or anyone else's active converters most likely), and be more reliable. Back in the old days, Western Electric 111C repeating coils were supplied by the telco for program audio lines. Look around broadcast transmitter sites and old studios, you'll probably find a few nailed up to the telco backboard that the LEC no longer has an interest in maintaining ownership of... The common mode rejection of Henry matchboxes isn't all that great, I've tested them. If you can, keep the audio level high on the sending side (I think 111C's were good up to close to a watt at 600 ohms!), and pad it down on the far side's secondary as necessary to maximize S/N. --- Jeff WN3A -- mailto:o...@ozindfw.net Rich Osman N1OZ POB 93167 Southlake, TX 76092 (Near DFW Airport)
Re: [Repeater-Builder] Digest Number 7130
I agree! I just made another post and I definitely agree the transformers are the better route over active devices for long audio runs. The active devices are best suited for interfacing un-balanced devices to balanced connections in a production or control room. I am thinking of running a cable that has several shielded audio pairs between the two locations to give me room for future needs and to carry ptt and cor signals. This is an example of what I am thinking of using for cable... http://www.gepco.com/products/proav_cable/analog_audio/multi_gf22_M.htm -- Original Message -- Received: Sat, 27 Feb 2010 09:21:39 AM PST From: Al Wolfe k...@arrl.net To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Digest Number 7130 John, You will save yourself a lot of grief by using real transformer isolation at each end in addition to balanced lines. The $12 dollar ones at RS will work fine for communication audio frequencies. If you want to go first class find some WE111 repeat coils. For wire CAT 5 will work and give you four pairs to play with. Some E and M signaling or COR maybe.? Al, K9SI, retired BC engineer (now occasional highly paid consultant) LOOONG audio runs Posted by: JOHN MACKEY jmac...@usa.net jmackey_usa_net Date: Fri Feb 26, 2010 10:49 pm ((PST)) I have a odd situation where I need to run long audio cables between my repeater controller and two repeaters. In this case, the repeater controller will be connected to 2 repeaters in the same cabinette. The other two repeaters will connected thru about 140 feet of wiring to the other side of a building. I am thinking of using balanced audio wires for the long runs and using Henry Engineeering boxes to convert between balanced/un-balanced at each end. Anyone ever done long audio runs like this? Am I over engineering it and unbalanced will be good enough? I use the Henry Engineering boxes for several audio conversions in broadcasting, here is a link for what they are: http://www.henryeng.com/matchbox.html
[Repeater-Builder] Re: West Coast Electronics
--- In Repeater-Builder@yahoogroups.com, skipp025 skipp...@... wrote: hybridfan wa6osb@ wrote: OK, since we've activated the Wy Back Machine again, does anyone remember the VHF high band West Coast Electronics remote mount mobiles? I'm still looking for photos of the radio, especially an interior picture and control head. These were built in Los Angeles, used an 832A in the final and had silver plated tuned lines in the receiver rf stages. I know San Diego Yellow Cab used them in the early 60's. That's how we got our FM start down here. The model was MFM 15-150B. Ken No good deed should go unpunished... I asked Geoff who operates a very nice CHP History web page at: http://www.wb6nvh.com/ ... and he replied with the following. [pasted text] West Coast Electronics was a division of, or somehow hooked up with, Mobile Communications Company of Los Angeles. It is my understanding that they were wholly owned by Yellow Cab and existed from only about 1949-54, more or less. Apparently Yellow Cab did not like paying the prices Motorola and GE were asking for their gear. They never branched out to public sales, as far as I can tell, as no one has seen an example with ownership documentation other than a Yellow Cab franchise somewhere. They made at least two mobile radios, a two-piece and a one-piece set. Dynamotor powered. Quite a bit smaller than Motorola, and cheaper in design. As Ken says, they used an 832 in the PA, probably because 832's were available on the war surplus market for about fifty cents at the time. The control head, at least the one I saw on an old Superman serial (!) was just a square box with pilot lamps and a volume control, with a Western Electric F3 handset hanging across the lower portion. I have an example of the transmitter from a two piece set and can send you photos when I find what I did with them. They are probably in my computer at home. In a true comment of what it is often like working in an independent mobile shop, my transmitter, tagged with Yellow Cab of Salinas, California had a yellowed scrap of paper wadded up and crammed inside the crystal oven. Written in pencil, the note on it says: Unable to warp back on frequency. He made me use it anyway. [end of pasted text] cheers, skipp Thanks for the additional info Skipp. The ones we had were the single piece R/T unit. Vibrator supply and 15 watts RF output. I think the dynamotor versions were 25 watts. I have the manual for them, but no pix. It does have the pictorial layout of the transmitter and receiver strips though. No mention is made of Yellow cab in the manual. Date on the schematic is Dec 1950. WCE's address was 1601 South Burlington Ave. Los Angeles 6, California. I guess Yellow Cab had them in service for quite a while, as I believe they were changing them out in the 1962-1963 time frame. We got 'em for $20 each at the time and gave us a start in FM in S.D. Ken
