OK -- well it is my experience that the first should be less than the final. All you are doing on the first go around is seating the metals and in the last you are doing a final mating - assuming the readings of the first mating meet specs.
But that may be different now that the material types have had a few years and a long way to progress since I actually did it last as a profession. I am always open to correction when it comes to electronics or rf, especially high freq stuff. :0) TNX Bob http://www.qsl.net/ke5cty KE5CTY (New Call) Old calls WB5ZQU - WY5L ----- Original Message ----- From: "Eric Lemmon" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Wednesday, May 25, 2005 10:27 PM Subject: Re: [Repeater-Builder] hardline connector generated IMD > Bob, > > The specified torques on Andrew Bulletin 237458 REV A are the same for > first and final tightening: 18-22 ft-lb. > > 73, Eric Lemmon WB6FLY > > KE5CTY Bob wrote: > > > Do the instructions mention anything about torque settings for > > tightening versus re-tightening? > > > > TNX, > > BOB > > KE5CTY (old calls WB5ZQU - WY5L) > > http://www.qsl.net/ke5cty > > > > > > > > -----Original Message----- > > From: [email protected] > > [mailto:[EMAIL PROTECTED] On Behalf Of Eric Lemmon > > Sent: Wednesday, May 25, 2005 8:03 PM > > To: [email protected] > > Subject: Re: [Repeater-Builder] hardline connector generated IMD > > > > Skipp, > > > > Verrry interesting! By curious coincidence, the installation > > instructions for the new Andrew Heliax connectors states that the > > connector must first be tightened and then removed to inspect the flare > > before re-tightening. I understand that the advice against re-using > > connectors is probably directed toward re-use of connectors that have > > been in service for some time, but the distinction should be made that > > merely tightening the connector once does not necessarily preclude > > tightening it a second time. (I, too, reuse expensive Heliax > > connectors!) > > > > 73, Eric Lemmon WB6FLY > > > > skipp025 wrote: > > > > > I saw a Sinclair demo at IWCE Las Vegas last > > > month about intermod from new & re-used > > > hardline connectors. > > > > > > Wrong re-use & assembly of a typical hardline > > > connector can be a serious IMD Generator, both > > > new and used. Who would have thought..? > > > > > > The major idea that I can pass along to most of > > > you is: Once you tighten a hardline connector > > > down, you should not reuse the same hardline end > > > position again. Cut off even the once used end > > > section & start with a new un-used end. > > > > > > "Cut off the portion of the hardline which had the > > > connector removed and place any new/used connectors > > > on virgin hardline end-sections." It might be > > > expensive or not practical, but it could save your > > > bacon on a busy mountain top. PIM is a real > > > Bxxxh (ryhmes with itch) to find and fix. > > > > > > The fly in the soup is the first-use grooves & > > > scratches created in the hardline metal, which > > > become serious PIM (Intermod) generators within > > > the actual connector (both new and used). > > > > > > Some of you re-using old hardline might be shooting > > > yourself in the foot right from the starting gate. > > > Again, if you assemble a new or used hardline run, > > > try to use new virgin cable ends only once. > > > > > > The real trouble is mostly sourced around the > > > center pin connection in relation to the hardline > > > in 7/8, 1-1/4, 1-5/8 and similar runs. But examples > > > of 3/8, 1/2 and smaller PIM generators were given. > > > > > > One thing about the Sinclair RF Engineers, they > > > really know their stuff well. Expensive but well > > > worth their prices. If you visit the Sinclair web > > > pages, notice they do specialize in antenna versions > > > for problematic PIM sites. > > > > > > **** > > > > > > Not related to Sinclairs information, I will say that > > > I do reuse some expensive connectors and hardline > > > ends after inspection and cleaning. > > > Said cleaning is with a brass or stainless brush. Stay > > > away from steel cleaning brushes. > > > > > > That's about it... still trying to get that great > > > Dayton hotdog tent smell out of my head. > > > > > > chow for now > > > skipp > > > > > > skipp025 @yahoo.com > > > www.radiowrench.com > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > 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/
