[Amps] 5 Minutes for Ameritron 811H to warm up?

[Carl]

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From: "Bill Turner" <dezrat at outlook.com>
Sent: Friday, January 23, 2015 9:06 PM
To: "Amps group" <amps at contesting.com>
Subject: Re: [Amps] 5 Minutes for Ameritron 811H to warm up?

> ------------ ORIGINAL MESSAGE ------------(may be snipped)
>
> On Sat, 24 Jan 2015 10:40:33 +1030, Leigh wrote:
>
>>Consequently a matched pair or quad set of reputable brand vintage NOS 
>>811A
>>/ 572B tubes are worth their weight in gold....and highly sought after.
>
> REPLY:
>
> It bothers me to see hams wasting their time and money on tubes made
> of glass. This is an obsolete technology which is of historical
> interest but really has no place with modern amateur radio.
>
> Ceramic tubes are far superior to glass, period. Yes, they are more
> expensive but so what? Good stuff costs more. Always has and always
> will.
>
> Please do yourself a favor. Save your nickels and dimes, get a second
> job, mow lawns or do whatever it takes but get something that works
> great and if not abused, lasts essentially forever.
>
> Ceramic is your friend.
>
> Bill W6WRT


There are likely more ceramic tubes out there that are as bad and worse than 
a lot of Chinese glass tubes.

OTOH there are plenty low cost USA made glass tubes that provide a decent 
SSB signal in GG.

4-125A, 4-250A, 4-400A, 4-500A, PL-175, 813, 803, 5-400A, plus similar 
European and Russian clones or originals.
My 1986 date code Eimac 3-500Z's havent shown any loss of power or gas since 
new and that's been a lot of hard use.

A little research will pull out a few more along with circuits and parts 
lists.

All Ive listed are rugged and not prone to easy damage by normal mistuning 
or wrong bandswitch/antenna selection, as are the so called "lasts 
essentially forever" ceramic versions. Indirectly heated ceramic tubes also 
have a comparatively short useful life.
Just the external circuitry to completely protect an 8877, 3CX800A7, 
4CX1000A and 4CX1500B plus their Chinese FU counterparts are just a few 
examples of what is in currently produced amps. Several require expensive 
sockets plus forced air cooling instead of a simple fan.

Just food for thought.

Carl
KM1H