[Amps] Pulls?

[Jeff AC0C]

I don't think PULL has a generic meaning.  How can you generalize with so 
many different tubes in so many different applications and with different 
thresholds for determining when to swap?  You can find stories on both 
ends - success and fail.

My only experience with pulls is with some YC156 that K5AND Dick sent to me 
to test in my amp as he was thinking about selling those.  I have a new 
(NOS) tube here for reference and 3 out out of the 4 pulls exhibited exactly 
the same power output with exactly the same Ig as the new tube.  I don't 
know how much "life" would be left in them from a ham amp standpoint but 
they were 100% as far as I could determine.  The 4th had some sort of 
internal short.  My experience with the YC156 pulls is pretty good based on 
this single data point.

73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie

-----Original Message----- 
From: RAY FRIESS
Sent: Wednesday, December 07, 2016 6:44 PM
To: amps at contesting.com
Subject: Re: [Amps] Pulls?

Speaking of pulls ..   I was a broadcast engineer about 35 years ago and we 
would regularly pull tubes when they were down to about 90% of their rated 
readings in the transmitter.  We would throw them out and replace them with 
new ones, until I started saving the pulls and taking them home.

As a result, I have about a dozen 4-125 and 4-250 tubes which were primarily 
used in the modulator section of our 5 KW transmitter.   They have been in 
storage at my home ever since and are still, for all intents and purposes, 
brand new.  They look brand new even, considering that they were replaced 
when they were at 85 to 90% efficiency.  I kept them thinking they would 
work great for ham linears for anyone who was building a linear.


If there is any interest, let me know.....   Most of them I rewrapped in 
their original padding and put back in their original boxes and stored in a 
safe place.


________________________________
From: Amps <amps-bounces at contesting.com> on behalf of Catherine James 
<catherine.james at att.net>
Sent: Wednesday, December 7, 2016 9:50 AM
To: amps at contesting.com
Subject: Re: [Amps] Pulls?

And how do you find these deals when broadcast stations with older 
transmitters do a pull?

I hear a lot of discussion around how great pulls are as an affordable 
source of good tubes, but it is always vague and never tells us how we can 
get in on the fun.  Is this one of those "you have to know somebody" 
situations?

73,
Cathy
N5WVR

--------------------------------------------
On Wed, 12/7/16, Fuqua, Bill L <wlfuqu00 at uky.edu> wrote:

Subject: RE: [Amps] Pulls?
To: "Catherine James" <catherine.james at att.net>
Date: Wednesday, December 7, 2016, 4:25 AM

   Most pulls today are from broadcast stations using older transmitters. 
Also, from SK estates.
73
Bill wa4lav
________________________________________
From:
Amps [amps-bounces at contesting.com]
on behalf of Catherine James [catherine.james at att.net]
Sent: Tuesday, December 06, 2016 11:13 PM
To: Amps Group
Subject: [Amps]
Pulls?

Where do you guys get your tube pulls?

I see many, many mentions of pulls from medical or other devices,
but I have never seen these offered. Have they dried up? Or
do they all go up on eBay at crazy prices?

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