Another mystery solved! 

My (late) father-in-law spent most of his career at Varian-Eimac, mostly 
working on TWTs, BWOs, and the occasional magnetron. In one batch of his 
goodies, along with the H&S SMA torque wrench, was a little box with some 
tapered metal pins! I've wondered what those were for, and now I know! 

He was very happy when his daughter brought home someone who knew what vacuum 
tubes were, even if he did think that the RF work I did as a ham, even the 144 
and 440 MHz stuff, was still practically DC... 

Bob K6RTM 
------------------------------ 

Message: 2 
Date: Mon, 20 Sep 2010 08:19:25 +0000 
From: Kit Scally <[email protected]> 
Subject: [time-nuts] WG mounting h/w (2) 
To: "[email protected]" <[email protected]> 
Message-ID: 
<[email protected]> 
Content-Type: text/plain; charset="us-ascii" 


Hi, 


Well, still not strictly, strictly true ! 
In Ku & K band earth stations I've worked in, I've never seen shoulder screws 
used, although the equipment used was mainnly from the USA. 
Next to you precision adaptors, SMA torque wrenches etc in your personal goodie 
box are sets of tapered pins, about 35-40mm long - that fit various diameter WG 
mounting holes (the old metric vvs Imperial issue again). 

You insert a pair of pins on diagonal corners then add bog-standard SS hardware 
to the opposite diagonals & tighten. The tapered pins are then removed and 
replaced with another pair of screws/nuts. This ensures absolute (?) internal 
WG slot alignment. There are a few variations on this theme if you must have 
absolutely minimum RL within that section of guide or if one guide face is 
threaded. Hex-headed bolts are usually used. 

That may explain why shouldered bolts are seldom seen. 

Tapered WG pins fall into the 99.9999% unobtainium class of materials. 


Kit 
VK2LL 

_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Reply via email to