Amps
[Top] [All Lists]

Re: [Amps] doorknob cap suppliers ?

To: "Jim W7RY" <w7ry@inbox.com>
Subject: Re: [Amps] doorknob cap suppliers ?
From: Robert Harmon <k6uj@pacbell.net>
Date: Sat, 19 Mar 2011 11:32:54 -0700
List-post: <amps@contesting.com">mailto:amps@contesting.com>
Jim,

My amp is an Alpha 76CA converted to two 3CPX800's


Bob
K6UJ





On Mar 19, 2011, at 11:20 AM, Jim W7RY wrote:

> What is "that amp" ? The model is not mentioned anywhere in this cut down 
> thread.
> 
> 73
> Jim W7RY
> 
> 
> 
> --------------------------------------------------
> From: "Carl" <km1h@jeremy.mv.com>
> Sent: Saturday, March 19, 2011 5:20 AM
> To: "Robert Harmon" <k6uj@pacbell.net>
> Cc: <amps@contesting.com>
> Subject: Re: [Amps] doorknob cap suppliers ?
> 
>> If the RFP doorknobs are the standard CRL/HEC HH-58 size there is no
>> difference between the 5 and 7.5KV versions except for the label. Both are
>> conservatively rated and just the overhead margin is different.
>> 
>> The weak link in that amp is the 160M switch contact to the frame screw as
>> Ive mentioned earlier.
>> 
>> Carl
>> KM1H
>> 
>> 
>> ----- Original Message ----- From: "Robert Harmon" <k6uj@pacbell.net>
>> To: "Carl" <km1h@jeremy.mv.com>
>> Cc: <dezrat1242@yahoo.com>; <amps@contesting.com>
>> Sent: Friday, March 18, 2011 10:01 PM
>> Subject: Re: [Amps] doorknob cap suppliers ?
>> 
>> 
>> Carl,
>> 
>> I hear what you are saying on higher voltage caps and yes it is cramped, I
>> checked the available room
>> and there really isn't any room for adding much larger caps.
>> RF Parts has some ceramic doorknobs in stock that look suitable.  They are
>> 2000pf at 7.5kv and they are about 7/8" in diameter. A pair of these
>> conected in parallel would fit o.k.
>> 
>> No steel or stainless, I am thinking of using 3/8" wide copper strap for the
>> doorknobs. I would love to find some
>> silver plated strap like the plate strap is,  but maybe getting too carried
>> away.
>> 
>> 
>> Bob
>> K6UJ
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> On Mar 18, 2011, at 1:42 PM, Carl wrote:
>> 
>>> I see no reason to go higher voltage in that amp. Similar B+ level
>>> products have been using the standard 5KV ceramic doorknob for many
>>> decades. The antenna safety chokes are there for a reason and if there is
>>> an antenna fault while transmitting saving the 8874's will be your major
>>> concern....always monitor the grid current.
>>> 
>>> With Russian caps you first need to have the room which is already
>>> cramped, and metric brass or screws and washers....you arent going to use
>>> steel or stainless are you?
>>> 
>>> Carl
>>> KM1H
>>> 
>>> 
>> 
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>> 
>> 
>> 
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>> Version: 10.0.1204 / Virus Database: 1498/3515 - Release Date: 03/18/11

_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>