[Top] [All Lists]

Re: [Amps] How to read the 3-500Z spec sheet?

To: "Larry" <>, <>
Subject: Re: [Amps] How to read the 3-500Z spec sheet?
From: "Carl" <>
Date: Sun, 23 May 2010 17:59:01 -0400
List-post: <">>

> On 23-May-10 1:56 PM, Carl wrote:
>> If the average ham simply reduced the power of his ricebox to 75-80% of 
>> its
>> ratings he would pick up a 3-6dB IMD improvement at least. Then he can 
>> use a
>> decent amp instead of operating in GIGO mode.
>> Carl
>> KM1H
> This only works if the amps is tuned for max carrier power and then the
> drive is reduced so that the PEP output power is 20-25% less than the
> carrier tune up power. Otherwise if the amp is tuned for the lower
> power, there isn't much difference. Doubt it? Hook up your spectrum
> analyzer and check it.
> 73, Larry

You start by reducing the internal low level drive control so that the panel 
control doesnt go beyond 80W for a 100W rig. You can fine tune by adjusting 
the bias a bit more towards Class A; just enough so the heat sink temp 
doesnt change.

The exercise is to drive an already clean amp with a lower IMD signal. 
Perhaps you dont understand GIGO.

Ive run that way and SA measured the results in many rigs going back to the 
days when when the TS-930 was new. The amp is happier also since the 
LK-500ZC I bought new in 86 still has the original tubes and loafs at 1200W 
instead of 1400W. The MLA-2500 on the second station also thanks me as it 
also runs the original 8875's. The current HF SSB/CW exciters are modified 
TS-940's which have excellent IMD.


Amps mailing list

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