Re: [Repeater-Builder] Re: Loss through adaptors:
http://pages.cthome.net/fwc/NAV-MFG.HTM Lists some of the military codes to indicate who made an item. 73 Glenn WB4UIV At 03:15 PM 02/02/06, you wrote: I think the biggest problem that we face is that our adaptors tend to not have a pedigree. I have some that I know were from Radio Shack, some that I bought at hamfests in boxes of stuff, some with real pedigrees (amphenol, in the bag) and some that are precision test equipment in their own right. If cost were no object, we would do the whole thing in hardline and GPC-7 connectors and be done with it, right? :) Someone mentioned before, an elbow or tee that used a SPRING to make the connection.. Boy, I would love to put that on my SA and see the plot! Probably works nicely at some frequencies, and insanely badly at others. I ended up having to put at least one right angle in every radio connection. The daniels gear uses front panel N connnectors, and there's no way I could close the cabinet door without RA connectors. I couldn't find anything RA in N, so I used a single RA adaptor on each of the four lines. Not sure who makes them. Markings are CQA or CGA and UG-27/U Definitely silver plated. Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: Loss through adaptors:
Dave, About 2 yrs ago I picked up several Type-N right angle connectors made by Andrew from an eBay auction. I will look when I get home this evening to see if I have any left so I can get the part number for you. The connectors were made specifically for FSJ1-50. 73 Mike Perryman www.k5jmp.us -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of Dave VanHorn Sent: Friday, February 03, 2006 12:06 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Loss through adaptors: --- In Repeater-Builder@yahoogroups.com, Eric Lemmon [EMAIL PROTECTED] wrote: Dave, Tessco carries right-angle N connectors from several manufacturers. Go here: http://www.tessco.com/products/displayProducts.do? groupId=410subgroupId=30 and look at pages 3 and 4. Another manufacturer of right-angle N connectors is Delta. Yes, but do they work with FSJ1-50? Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: Loss through adaptors:
I found them on the Tessco website... here is the link.. http://www.tessco.com/products/displayProductInfo.do?sku=417130eventPage=1 73 Mike Perryman www.k5jmp.us -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of Mike Perryman Sent: Friday, February 03, 2006 2:04 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Loss through adaptors: Dave, About 2 yrs ago I picked up several Type-N right angle connectors made by Andrew from an eBay auction. I will look when I get home this evening to see if I have any left so I can get the part number for you. The connectors were made specifically for FSJ1-50. 73 Mike Perryman www.k5jmp.us -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] Behalf Of Dave VanHorn Sent: Friday, February 03, 2006 12:06 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Loss through adaptors: --- In Repeater-Builder@yahoogroups.com, Eric Lemmon [EMAIL PROTECTED] wrote: Dave, Tessco carries right-angle N connectors from several manufacturers. Go here: http://www.tessco.com/products/displayProducts.do? groupId=410subgroupId=30 and look at pages 3 and 4. Another manufacturer of right-angle N connectors is Delta. Yes, but do they work with FSJ1-50? Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: Loss through adaptors:
Dave, Tessco carries right-angle N connectors from several manufacturers. Go here: http://www.tessco.com/products/displayProducts.do?groupId=410subgroupId=30 and look at pages 3 and 4. Another manufacturer of right-angle N connectors is Delta. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Dave VanHorn Sent: Thursday, February 02, 2006 12:16 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Loss through adaptors: I think the biggest problem that we face is that our adaptors tend to not have a pedigree. I have some that I know were from Radio Shack, some that I bought at hamfests in boxes of stuff, some with real pedigrees (amphenol, in the bag) and some that are precision test equipment in their own right. If cost were no object, we would do the whole thing in hardline and GPC-7 connectors and be done with it, right? :) Someone mentioned before, an elbow or tee that used a SPRING to make the connection.. Boy, I would love to put that on my SA and see the plot! Probably works nicely at some frequencies, and insanely badly at others. I ended up having to put at least one right angle in every radio connection. The daniels gear uses front panel N connnectors, and there's no way I could close the cabinet door without RA connectors. I couldn't find anything RA in N, so I used a single RA adaptor on each of the four lines. Not sure who makes them. Markings are CQA or CGA and UG-27/U Definitely silver plated. Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: Loss through adaptors:
I have issues with crimp-on connectors. I have seen too many of them pull apart when used as pigtails to tower mounted antennas.I have also seen the braid break right at the crimp. Blame it on improper crimping or the human element or whatever,but I will use the clamp style connectors. I seem to be able to get more consistent results and better mechanical strength. I agree with all the other points and will add proper weatherproofing to outside connections with vapor wrap and Scotch tape topped off with Scotchkote. 28 years with a large RCC taught me what works and what doesnt,lessons learned the hard way are not soon forgotten! 73,Lee,N3APP Eric Lemmon wrote: This topic interests me, not just because I personally abhor adaptors in any repeater system, but also because I see that others are equally passionate about certain cables. After spending many years troubleshooting repeater systems cobbled together by my friends and colleagues, most of which were replete with every connector series known to Mankind- and which used many adapters to mate between series- I became aware that the most troublesome repeaters had the largest number of adapters. When I began to design my own repeater systems, I vowed to abide by three simple rules: 1. Use only Mil-spec RG-400/U or RG-214/U cable for jumpers and interconnecting cables, and 2. Make up these cables with the correct connectors on each end, using the specified tools, and 3. Use only crimped connectors with silver-plated brass bodies, gold-plated contacts, and Teflon dielectric. None of my systems have adaptors or barrel connectors, since the cables are made up to fit the job. There are no BNC or UHF connectors; except for very unusual situations, all connectors are Type N with a few mini-UHF needed to mate with a particular radio. It would not occur to me to use an adapter to mate a male N connector to a UHF female connector- I would have a premium UHF male connector on that end of the cable! Of course, this only is an issue with older radios and duplexers; the modern counterparts have female N connectors. I guess the bottom line here is that almost all double-shielded and 100% shielded cable will perform superbly in a repeater system, if properly installed. I have never heard of any repeater system that was significantly improved by replacing RG-214/U with 3/8 hardline, Superflex, or any other trendy cable- unless the original installation was flawed. We should all be ready to accept that a flawed installation does not condemn a cable brand or type. In my personal opinion, the use of adapters in place of the exactly correct connectors leads to a flawed installation. YMMV! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Jay Urish Sent: Monday, January 30, 2006 7:04 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Loss through adaptors: Yea, I use the heck out of LMR-400UF.. Please enlighton me! Dave VanHorn wrote: For tight spots, consider superflex 1/4 or 3/8 in hard line. I actually use the mini 141 rigid line for modest power levels. FSJ1-50 now in every cable except my adaptor mess (soon to be replaced) and the 2M duplexer harness. Avoid trying to use foam center cables where possible. My FJS1-50 is foam, what's the beef with foam? 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: Loss through adaptors:
Nice test results! Confirms my beliefs! Would be nice to have a list of the worst/best connectors for those not fortunate enough to have the proper test equipment. Would make a good pocket guide when hamfesting!!! 73,Lee nj902 wrote: --- In Repeater-Builder@yahoogroups.com, skipp025 [EMAIL PROTECTED] wrote: I lifted the below text from the yahoo rfamplifiers group page, posted this last week by my friend Dave. It's right on the money. http://groups.yahoo.com/group/rfamplifiers/ [paste] If you are able to measure the SWR of a coax connection at VHF, then you've installed a connector wrong. I used an HP 8510C network analyzer to measure a whole bunch of UHF to N, UHF to BNC and so forth, adapters, all stacked on top of each other to a foot long, and the lowest frequency where I measured anything of concern was at 2 GIGAhertz, where the SWR rose to 1.1:1. Yes, I know, amateur radio lore is full of the claim that UHF connectors are awful. They are, but only if you compare then to BNC and N, which are suitable for 10GHz and above. Assembled correctly, a UHF connector is invisible below 1GHz. [end] I hope nobody is buying into this BS. Connector and adapter mis-match and loss issues are hardly amateur radio lore RF manufacturers and instrumentation companies have stressed this for years - justifiably. It's easy to verify if you have access to instrumentation. Just out of curiosity I decided to run a couple of tests. When you measure a device for SWR you are actually measuring return loss. You can do this on a network analyzer or with a spectrum analyzer and tracking generator plus a signal separation device such as a return loss bridge or directional coupler. I decided to try both instruments and compare the results. You first calibrate the measurement setup with precision components from your cal kit [e.g. Agilent 85032B]. The critical component is a precision 50 ohm load. With a good bridge or coupler you should be able to measure a return loss of 40 dB or greater [equivalent to an SWR or 1.02:1] Normally your instrument test ports will be type N although some instruments have APC-7 test ports. Your cal kit should match the test ports. I started with a full 2-port cal of the VNA and a normalization of the Spectrum analyzer. My reference load did measure as expected. The next step is to insert the device under test. In this case we are interested in looking at a UHF connector. Obviously, since the instrument is type N, we have to use adapters. Just out of curiosity, I decided to compare two pairs of adapters. First an NF-NF mated to an NM-NM. [UG-57B/U and UG-29B/U] This created an insertable device. These are standard adapters as opposed to precision components and as expected, there was some degradation of the return loss measurement. I then compared this to two other adapters, NM to UHF-F and UHF-M to NF [UG-146/U and UG-83/U], again creating an insertable device This pair has just a single UHF male to female junction and results in a significant decrease in return loss [i.e. increase in SWR.] I also tried inserting an 90 degree UHF adapter [UG-646/U] in line between the UG146/U and the UG83/U which resulted in further [significant] return loss degradation. I measured several sets of these parts and the results were not only consistent from part to part but generally match within a few tenths of a dB between the VNA and the spectrum analyzer. I always like to see comparable results from two significantly different instrument setups - it confirms your thought process and results. Results at: 150 MHz, 450 MHz, 900 MHz NM-NF adapters: [VNA]: 36 dB, 35 dB, 31 dB [SA/TG] 37 dB, 35.7 dB, 30 dB N-UHF + UHF-N adapters: [VNA]: 26 dB, 16.5 dB, 11.4 dB [SA/TG]: 23.6 dB, 17.2 dB, 11.5 dB N-UHF + UHF 90 + UHF-N [VNA]: 20.2 dB, 12.03 dB, 9.3 dB [SA/TG]: 21.6 DB, 11.9 dB, 9.1 dB Now just for reference, a return loss of 11 dB would be equivalent to an SWR of 1.785 : 1 [ONE UHF junction @ 900 MHz] and a return loss of 17 dB would be an SWR of 1.329 : 1 [@ 450 MHz] UHF connectors invisible below a gigahertz??? Hardly. Also - someone asked about the 90 degree N fitting at 900 MHz so I tested a few of those. That's easy because being M on one side and F on the other, it is inherently insertable The round kind [UG-27A/U] averaged return loss of 22 dB. The square ones[UG-27D/U] are better at 27 dB [1.094 : 1 SWR] 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: Loss through adaptors:
nj902 wrote: Connector and adapter mis-match and loss issues are hardly amateur radio lore RF manufacturers and instrumentation companies have stressed this for years - justifiably. BTW, I am told Motorola derated 'N' connectors a few years ago. They are not putting 'N' connectors on any path that carries tranmit power (not sure how much) above 800 Mhz. They are using 7/16 DIN for 800/900Mhz transmitters of late. I do know that 250W at 931 Mhz through an 'N' connector gets warm to the touch. -- Jim Barbour WD8CHL Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: Loss through adaptors:
At 1/31/2006 04:56 AM, you wrote: Nice test results! Confirms my beliefs! Would be nice to have a list of the worst/best connectors for those not fortunate enough to have the proper test equipment. Would make a good pocket guide when hamfesting!!! 73,Lee N-UHF + UHF-N adapters: [VNA]: 26 dB, 16.5 dB, 11.4 dB [SA/TG]: 23.6 dB, 17.2 dB, 11.5 dB I measured some N-UHF pairs a while back found quite a variation in return loss. The best ones had Teflon dielectric in the UHF side had a R.L. of 20 dB. The worst one had brown dielectric. Bob NO6B 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: Loss through adaptors
At 1/31/2006 11:04 AM, you wrote: It was not teflon, it was some unknown thermo-polymer with a very low melting point! Yeah, I've hit these too.. They look like silver plated, and the dielectric is a little pink-ish like teflon. Icky. Me three. PL-259 connector I bought at the Rochester Hamfest. Melted so badly that it was completely unusable. Sure looked like Teflon when I bought it. Bob NO6B 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: Loss through adaptors:
Yea, I use the heck out of LMR-400UF.. Please enlighton me! Dave VanHorn wrote: For tight spots, consider superflex 1/4 or 3/8 in hard line. I actually use the mini 141 rigid line for modest power levels. FSJ1-50 now in every cable except my adaptor mess (soon to be replaced) and the 2M duplexer harness. Avoid trying to use foam center cables where possible. My FJS1-50 is foam, what's the beef with foam? -- Jay Urish W5GM DCARA President ARRL Life Member TXFCA President ERS Vice-Prez Denton County ARRL VEC N5ERS VP/Trustee Monitoring 1292.30Ghz PL-100.0 441.375 PL-88.5 and 444.850 PL-88.5 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: Loss through adaptors:
The EIA and TIA both have a spec that virtually all cable manufacturers hold to. The static minimum bend radius of any cable that meets their spec is 10XD or ten times the diameter of the outer jacket. Under pulling load that radius doubles to 20XD. The individual manufacturer will state the maximum pulling force. I've never had any problems if I adhere to that spec. And I deal with all sorts of cabling from heliax to precision HD video coax. Rod Lane, N1FNE Senior Systems Engineer ESPN Systems Engineering -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Dave VanHorn Sent: Monday, January 30, 2006 8:02 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Loss through adaptors: In sharp bends, the softer center foam conductors will migrate from the center over time and with modest heat. Feedline/coax with soft foam centers outside in the summer sun is a serious potential trouble maker. Define sharp. the min bend radius is 1 and none of my outside stuff is less than 12. Indoors I go down to 3 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/
