Tom,

A lot of good info here so far.   I think I mentioned to  you off list 
last week that I had decided to use the THP SS amp   in the ARRL  CW 
contest, instead of the AL-80B primarily  because of the relay noise in 
the 80B.

I think the noise factor is just a matter of what  relays  are used in a 
particular amp, and  not a  tube vs. solid state issue.    In a  world 
where cost is king, it is just cheaper to use  the open frame relays 
like  we both have in our Ameritron amps.    The THP uses fast, quiet 
relays from Panasonic.   I can only hear it key if I put my ear to the 
case.   Of course, THP went bust 2 months ago,  so draw your own 
conclusions.

The QSK option from Ameritron is interesting, but is a few hundred 
bucks.   I think there are 2 choices: external, and an internal unit 
that can go into some (if not all) their amps.


Relay noise is something that drives one person crazy, and doesn't 
bother someone else.  I just find it annoying  over a long period.

73, Steve KW3A



On 2/23/2014 10:16 AM, Tom Behler wrote:
> Hi, all.
>
>
>
> Well, I'd now like to tap into the wisdom of the group on an issue I don't
> know a whole lot about, so please bare with me.
>
>
>
> As I think many of you know, I use an Ameritron AL811H tube-type amplifier
> with my TS590 HF setup.  I also have an ARB704 buffer box in the circuit, to
> protect the relay circuit in the TS590.
>
>
>
> I'm actually very happy with the setup, although tuning the amp can be a bit
> tricky at times, even with the TW1.
>
>
>
> Anyway, the AL811H has a relay circuit that is rather noisy when keying and
> unkeying.  This is apparent on SSB, and even more apparent on CW.  In fact,
> the noisy relay circuit is one of the main reasons I don't like to use the
> amp when in CW mode, due to the constant and rather annoying relay chatter.
>
>
>
> My question is this:  Do solid-state amplifiers have relay circuits in them
> that are as noisy, or do they tend to be quieter?
>
>
>
> There is no way I have the money in my budget right now to purchase a solid
> state amp, since I believe they can run into the thousands of dollars, but
> I'm wondering if this might be something for me to think about in the long
> term?
>
>
>
> I'm looking forward to all of your observations and suggestions.
>
>
>
> Tom Behler:  KB8TYJ
>
>
>
>
>