Re: [Repeater-Builder] Crimp versus Clamp Connectors
That's exactly what I have been thinking. Don't blame the connector just because someone installed it wrong or because they subjected it to a condition that they shouldn't have. I was at a two-meter repeater site not long ago helping chase down some issues. On top of the rack was discovered what was thought to be an unused coil of RG-8 cable. Nope. It was about 75' of coax that was sitting there between the duplexer and the heliax. When it was closer inspected, the shields were never soldered to the shells of the PL-259 connectors. Obviously the whole mess was a poor install, but to whomever left it that way, I'm sure that they left thinking they'd done everything right. Chuck WB2EDV Rod Lane wrote: You should probably not be looping those patch cables through cinder blocks before you attach them to the antenna. ;^) Seriously, the rated pull force for Amphenol Type N is on their web site at http://www.amphenolrf.com/products/typen.asp Cable Retention; Crimps: 60-120 lbs Clamps: 30-70 lbs. If you had this kind of problem, I'd sincerely suspect an installation issue. Improper strip length or crimping can lead to poor cable retention. Check you connector manufacturers' data sheet. 73 Rod Lane, N1FNE -Original Message- Subject: Re: [Repeater-Builder] Crimp versus Clamp Connectors From: Repeater-Builder@yahoogroups.com To: Repeater-Builder@yahoogroups.com To: Repeater-Builder@yahoogroups.com There is no knife edge against the braid,it is a clamping type connector that the braid folds over a stepped insert. I will relate my experience with crimp connectors when we decided to try them for the first time. We had put 22 antennas up on a 500' Rohn 65 tower with crimped on connectors on all the pigtails and 11 of them failed within a month. They had pulled out or had broken the shield braid at the crimp. We did a little non-scientific stress test on crimp vs. clamp pigtails by suspending a weight from the cable ,adding more until they failed. The clamp type took THREE TIMES as much weight before it let go.We also did a flex test and the crimp braid failed long before the clamp one did. That was all I needed to see to change my mind! All were replaced with mil-spec clamp style connectors and are all still in service 20 years after the fact. Company policy was implemented that required all outdoor connectors be mil-spec clamp type Amphenols at all 303 company tower sites. Now maybe you can get away with crimps on some sites,but not up north on the Great Lakes where winds are tough and ice is common. You quickly learn what works and what doesnt and you will NEVER convice me to use crimp on connectors again! I guess I'm old and set in my ways,for good reason 73,Lee Eric Lemmon wrote: 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] Crimp versus Clamp Connectors
Eric Lemmon wrote: Lee, I appreciate your comments, but I can rebut them easily. I have seen too many clamp-type connectors pull apart, usually because they were over-tightened during assembly. Take a close look at a MIL-spec clamp-type N connector, and you can see that the knife-edge component can slice right through the braid if the nut is over-tightened, allowing the cable and the center conductor to pull right out of the connector. snip Every Mil-spec clamp type N connector I have ever made put the knife edge towards the red gasket material, not the braid. See the scan of an original instruction sheet: http://testeqdocs.w4zt.com/nconnector/ 73, Tony W4ZT 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] Crimp versus Clamp Connectors
I just salvaged some silver amphenol BNCs and this was the case.On 2/1/06, Tony King, W4ZT [EMAIL PROTECTED] wrote:Eric Lemmon wrote: Lee, I appreciate your comments, but I can rebut them easily.I have seen too many clamp-type connectors pull apart, usually because they were over-tightened during assembly.Take a close look at a MIL-spec clamp-type N connector, and you can see that the knife-edge component can slice right through the braid if the nut is over-tightened, allowing the cable and the center conductor to pull right out of the connector. snipEvery Mil-spec clamp type N connector I have ever made put the knife edge towards the red gasket material, not the braid. See the scan of anoriginal instruction sheet: http://testeqdocs.w4zt.com/nconnector/73, Tony W4ZT 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/ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] Crimp versus Clamp Connectors
There is no knife edge against the braid,it is a clamping type connector that the braid folds over a stepped insert. I will relate my experience with crimp connectors when we decided to try them for the first time. We had put 22 antennas up on a 500' Rohn 65 tower with crimped on connectors on all the pigtails and 11 of them failed within a month. They had pulled out or had broken the shield braid at the crimp. We did a little non-scientific stress test on crimp vs. clamp pigtails by suspending a weight from the cable ,adding more until they failed. The clamp type took THREE TIMES as much weight before it let go.We also did a flex test and the crimp braid failed long before the clamp one did. That was all I needed to see to change my mind! All were replaced with mil-spec clamp style connectors and are all still in service 20 years after the fact. Company policy was implemented that required all outdoor connectors be mil-spec clamp type Amphenols at all 303 company tower sites. Now maybe you can get away with crimps on some sites,but not up north on the Great Lakes where winds are tough and ice is common. You quickly learn what works and what doesnt and you will NEVER convice me to use crimp on connectors again! I guess I'm old and set in my ways,for good reason 73,Lee Eric Lemmon wrote: Lee, I appreciate your comments, but I can rebut them easily. I have seen too many clamp-type connectors pull apart, usually because they were over-tightened during assembly. Take a close look at a MIL-spec clamp-type N connector, and you can see that the knife-edge component can slice right through the braid if the nut is over-tightened, allowing the cable and the center conductor to pull right out of the connector. That seldom, if ever, happens with a properly-applied crimp connector. Moreover, how often do you see a technician use a torque wrench to tighten the nut, per instructions? Most cable techs just wrench the nut until it doesn't move any more- and that's exactly where the faulty installation occurs. When the proper crimper is used, that cannot occur with a crimp connector. One of the first requirements of a jumper or cable installation is that there should not be any tension on the connector or the cable. I daresay that any connector, whether crimp or clamp, that pulls apart did so because of tension. DUH! A proper cable or jumper installation does *not* subject its connectors to tension, so there should be no case of connectors pulling apart! As far as consistent results, I think it's a wash. I recognize that an experienced craftsman can assemble and attach any connector consistently, time after time. But, time is money. I can install a crimp-type male N connector on a given type of cable in perhaps 1/2 or 1/3 the time it takes to install a MIL-spec clamp connector. On a complex job, this disparity may amount to several hours. If the project engineer knows that a high-quality crimp connector is just as reliable as a high-quality clamp connector, he or she will make the right choice. Since the N connector is a constant-impedance design, there should not be any impedance bump seen on a VNA, regardless of whether it is attached by crimp or by clamp means. I will admit that a crimp N connector is not waterproof to the degree that a MIL-clamp N connector is, but I don't install crimp N connectors outdoors without a multiple overwrap of bi-seal tape. The final installation is absolutely waterproof and reliable, as evidenced by several decades of performance. I happen to prefer silver/gold connectors made by RF Industries, but equally reliable crimp connectors are made by Amphenol, Delta, Huber+Suhner, and others. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Q Sent: Tuesday, January 31, 2006 4:53 AM To: Repeater-Builder@yahoogroups.com Subject: 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 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] Crimp versus Clamp Connectors
Never forget MIL-TDD-41 ... Neil - WA6KLA 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] Crimp versus Clamp Connectors
I have never had a clamp up style connector cut the braid. All the connectors I use on pro installs are clamp up style and never a joiner, adapter in sight. I was taught that if you don't the correct connector GET ONE no adaptors ever. This maybe is an old idea but for 30 years has worked for me. P.S. justhad a look at the duplexer pics on W4ZT and spied a Eastpenn gel battery these I use for back up power. Cheers from down under Brett - Original Message - From: Tony King, W4ZT [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 01, 2006 10:46 PM Subject: Re: [Repeater-Builder] Crimp versus Clamp Connectors Eric Lemmon wrote: Lee, I appreciate your comments, but I can rebut them easily. I have seen too many clamp-type connectors pull apart, usually because they were over-tightened during assembly. Take a close look at a MIL-spec clamp-type N connector, and you can see that the knife-edge component can slice right through the braid if the nut is over-tightened, allowing the cable and the center conductor to pull right out of the connector. snip Every Mil-spec clamp type N connector I have ever made put the knife edge towards the red gasket material, not the braid. See the scan of an original instruction sheet: http://testeqdocs.w4zt.com/nconnector/ 73, Tony W4ZT 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] Crimp versus Clamp Connectors
Tony, You are absolutely correct. It amazes me that anyone would install that component backwards, but some idiots do just that. I and many others have seen it happen. My statement would have been clearer, had I emphasized that excessive torque on the clamping nut will extrude the shield braid to the point that it is severely weakened. Any tension or side-to-side movement will almost certainly break the braid and allow the feedline to pull right out of the connector. I stand by my statement that a *proper* installation of any feedline or antenna connector should not have *any* tension imposed upon it, and should not allow *any* side to side movement of the cable at the connector. Whether a clamp type or a crimp type connector is resistant to flapping around in the winds of Montana is irrelevant; that connection should be secured so that it does not move! The posters who described instances of cables breaking at the shield crimp (or clamp) should, perhaps, be correcting their installations so that the cable has neither tension nor the possibility of movement. I submit that, if the above two conditions are met, braid breakage or separation cannot occur. When properly installed and waterproofed, the method of attachment should have little influence on the longterm reliability. As always, YMMV. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Tony King, W4ZT Sent: Wednesday, February 01, 2006 6:47 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Crimp versus Clamp Connectors Every Mil-spec clamp type N connector I have ever made put the knife edge towards the red gasket material, not the braid. See the scan of an original instruction sheet: http://testeqdocs.w4zt.com/nconnector/ 73, Tony W4ZT 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] Crimp versus Clamp Connectors
How did the installer get the braid ring installed backwards? In all of the Type-N connectors that I have installed on RG-214, The braid ring is relived so that it seats at the end of the insulation with the braid coming through and being fanned out. The person that installed the braid ring backwards could not have read any installation instructions for the connector. I sure would not want them doing ANY work for me. I have not had a Type-N connector fail, that I installed, due to braid fatigue. I have seen some sloppy installs. The center pin set to the wrong depth, destroying the female connector on first mate. I have even seen a Type-N connector with an attempt having been made to solder the braid to the braid ring. Where do these idiots come from?? 73 Glenn WB4UIV At 09:10 PM 02/01/06, you wrote: Tony, You are absolutely correct. It amazes me that anyone would install that component backwards, but some idiots do just that. I and many others have seen it happen. My statement would have been clearer, had I emphasized that excessive torque on the clamping nut will extrude the shield braid to the point that it is severely weakened. Any tension or side-to-side movement will almost certainly break the braid and allow the feedline to pull right out of the connector. I stand by my statement that a *proper* installation of any feedline or antenna connector should not have *any* tension imposed upon it, and should not allow *any* side to side movement of the cable at the connector. Whether a clamp type or a crimp type connector is resistant to flapping around in the winds of Montana is irrelevant; that connection should be secured so that it does not move! The posters who described instances of cables breaking at the shield crimp (or clamp) should, perhaps, be correcting their installations so that the cable has neither tension nor the possibility of movement. I submit that, if the above two conditions are met, braid breakage or separation cannot occur. When properly installed and waterproofed, the method of attachment should have little influence on the longterm reliability. As always, YMMV. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Tony King, W4ZT Sent: Wednesday, February 01, 2006 6:47 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Crimp versus Clamp Connectors Every Mil-spec clamp type N connector I have ever made put the knife edge towards the red gasket material, not the braid. See the scan of an original instruction sheet: http://testeqdocs.w4zt.com/nconnector/ 73, Tony W4ZT 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] Crimp versus Clamp Connectors
You should probably not be looping those patch cables through cinder blocks before you attach them to the antenna. ;^) Seriously, the rated pull force for Amphenol Type N is on their web site at http://www.amphenolrf.com/products/typen.asp Cable Retention; Crimps: 60-120 lbs Clamps: 30-70 lbs. If you had this kind of problem, I'd sincerely suspect an installation issue. Improper strip length or crimping can lead to poor cable retention. Check you connector manufacturers' data sheet. 73 Rod Lane, N1FNE -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Q Sent: Wednesday, February 01, 2006 3:11 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Crimp versus Clamp Connectors There is no knife edge against the braid,it is a clamping type connector that the braid folds over a stepped insert. I will relate my experience with crimp connectors when we decided to try them for the first time. We had put 22 antennas up on a 500' Rohn 65 tower with crimped on connectors on all the pigtails and 11 of them failed within a month. They had pulled out or had broken the shield braid at the crimp. We did a little non-scientific stress test on crimp vs. clamp pigtails by suspending a weight from the cable ,adding more until they failed. The clamp type took THREE TIMES as much weight before it let go.We also did a flex test and the crimp braid failed long before the clamp one did. That was all I needed to see to change my mind! All were replaced with mil-spec clamp style connectors and are all still in service 20 years after the fact. Company policy was implemented that required all outdoor connectors be mil-spec clamp type Amphenols at all 303 company tower sites. Now maybe you can get away with crimps on some sites,but not up north on the Great Lakes where winds are tough and ice is common. You quickly learn what works and what doesnt and you will NEVER convice me to use crimp on connectors again! I guess I'm old and set in my ways,for good reason 73,Lee Eric Lemmon wrote: Lee, I appreciate your comments, but I can rebut them easily. I have seen too many clamp-type connectors pull apart, usually because they were over-tightened during assembly. Take a close look at a MIL-spec clamp-type N connector, and you can see that the knife-edge component can slice right through the braid if the nut is over-tightened, allowing the cable and the center conductor to pull right out of the connector. That seldom, if ever, happens with a properly-applied crimp connector. Moreover, how often do you see a technician use a torque wrench to tighten the nut, per instructions? Most cable techs just wrench the nut until it doesn't move any more- and that's exactly where the faulty installation occurs. When the proper crimper is used, that cannot occur with a crimp connector. One of the first requirements of a jumper or cable installation is that there should not be any tension on the connector or the cable. I daresay that any connector, whether crimp or clamp, that pulls apart did so because of tension. DUH! A proper cable or jumper installation does *not* subject its connectors to tension, so there should be no case of connectors pulling apart! As far as consistent results, I think it's a wash. I recognize that an experienced craftsman can assemble and attach any connector consistently, time after time. But, time is money. I can install a crimp-type male N connector on a given type of cable in perhaps 1/2 or 1/3 the time it takes to install a MIL-spec clamp connector. On a complex job, this disparity may amount to several hours. If the project engineer knows that a high-quality crimp connector is just as reliable as a high-quality clamp connector, he or she will make the right choice. Since the N connector is a constant-impedance design, there should not be any impedance bump seen on a VNA, regardless of whether it is attached by crimp or by clamp means. I will admit that a crimp N connector is not waterproof to the degree that a MIL-clamp N connector is, but I don't install crimp N connectors outdoors without a multiple overwrap of bi-seal tape. The final installation is absolutely waterproof and reliable, as evidenced by several decades of performance. I happen to prefer silver/gold connectors made by RF Industries, but equally reliable crimp connectors are made by Amphenol, Delta, Huber+Suhner, and others. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Q Sent: Tuesday, January 31, 2006 4:53 AM To: Repeater-Builder@yahoogroups.com Subject: 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
