Amps
[Top] [All Lists]

Re: [Amps] triode or tetrode

To: amps@contesting.com
Subject: Re: [Amps] triode or tetrode
From: Roger <sub1@rogerhalstead.com>
Date: Fri, 27 Aug 2010 02:05:27 -0400
List-post: <amps@contesting.com">mailto:amps@contesting.com>

On 8/27/2010 1:39 AM, Bill, W6WRT wrote:
> ORIGINAL MESSAGE:
>
> On Thu, 26 Aug 2010 20:45:35 -0700 (PDT), Jim Hoge
> <knowkode@verizon.net>  wrote:
>
>> I haven't made up my mind as to buy or build. If I build, I know it will 
>> take me
>> too long to complete the project and I will have a tendency to upgrade
>> components above and beyond what would be adequate. I love to spend time in 
>> the
>> shop, perhaps as much as in front of the radio. I suspect that if I buy, I 
>> will
>> again be settling for less than I'd like. The short answer is I dunno.
>>
>> Jim W5QM
> REPLY:
>
> Actually, that's a very good answer. Shows you have really been
> thinking about it.
Agreed.
> If I may, here are a few thoughts I had when I went through the same
> decision making process:
>
> The first thing to answer for yourself is do I really want to build an
> amplifier or do I really just want to have an amplifier? In other
> words, is having a homebrew amp really important to me? Or is having a
> beautiful, commercially built amp plenty good enough?
>
It depends on what will satisfy you.  I chose both routes.  I've been 
collecting parts for some time...actually this is the second time for 
collecting parts.  At one time I had nearly every thing I needed, to 
build a real conservative legal limit plus amp even with spare tubes. I 
also had lots of test equipment left from when I was in amateur radio 
commercially (sales and service), but when I quit work to go back to 
college full time and get my pilot's license there were probably 10 to 
15 years I never turned on a rig. I sold off everything except a 
transceiver, the tower, rotator, tribander, and a couple of wire 
antennas. After college I worked 7 more years and then retired. Since 
then I've been becoming more active, purchased a good rig, restored some 
old Hallicrafters gear, picked up a couple of amps, decided I wanted a 
conservative legal limit amp with plenty of overhead and started 
collecting parts again. I purchased one of the nicest amps I've had, the 
Tokyo Hy-Power HL1.5Kfx.  Beautiful fit and finish, auto band switching, 
quiet, ran a KW out 1.8-30 MHz (800 watts on six) with almost no fan 
noise. It would run that power on those bands all day long with the only 
extra required being a second fan.

But, it really wasn't what I wanted so I sold it and purchased a real 
amp that would do the legal limit all day long in virtually any mode 
save maybe AM which I never operate.

NOW I'm aggressively chasing down parts to build either a 3CX3000, or 
more likely either a  4CX3000A7, or YC156.  Probably the 4CX3000 as I 
can play with circuits from 1.8 through the 144 MHz band.
> If having a homebrew amp is important, welcome to the club. I came to
> that decision and after literally years of collecting parts, building
> and discarding different designs and configurations, I finally have an
> amp sitting on my desk that is built like a tank, does all I want and
> one I am proud of. I built at least four amps before this one but none
> were quite good enough in one respect or another and they all got
The one I'm chasing will be my 4th as well, but the last one I built was 
a good 30 years ago.
> cannibalized for parts for the next one. There are a few parts in this
> amp that have been used and re-used for thirty years. I'm sure every
> long-term homebrewer knows exactly what I mean.  :-)
>
> But was that a good idea overall?  Financially, no. Just in terms of
> dollars and cents, I would have been way ahead to buy a good quality
> amp, use it as long as I wanted and eventually sell it. With any luck
> I could sell a really quality amp for near what I paid for it. The net
> cost of ownership would be relatively small compared to the countless
> dollars and hundreds if not thousands of hours I put into my homebrew
> amp projects over the years.
That was my conclusion as well.  I'm a bit of a perfectionist when it 
comes to building and when I get it finished I want it to look every bit 
as good as any commercial amp...save maybe the Japanese amps.
> But if I had just bought an amp I would have missed a great learning
> experience. I built my amp from scratch, not copying any existing
> design other than taking generic schematics from many sources. In
> doing it this way,I had countless little learning experiences that you
> never hear about or read about in books.
Interspersed with a few exciting moments.
>   Without doubt, I am far more
> knowledgeable about how an amp REALLY works than if I had just bought
> one and followed the owner's manual.  I made a lot of mistakes and I
> learned from every one. You can't get that kind of education in school
> or from books.
So now I'm looking forward to getting the equipment to make a 
professional looking panel as well as do a good job on the metal work in 
addition to building a circuit for HF, 6-meters, and two-meters.

I keep telling the locals the 4CX3000 is for packet and making sure I 
can get into the local repeater. <:-)) Occasionally some one comes along 
that really believes that.
> Enough rambling. I hope this helps with your decision. Either way you
> decide will be the right one for you. Good luck and keep us posted.
>
Likewise,

73 and good luck,

Roger (K8RI)
> 73, Bill W6WRT
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

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