>
>> Here is a point I've never seen discussed , anywhere, and I've often
>> wondered about it !!
>> what reason is there for a specific value of resistor in a
>> parasitic suppressor. ?? I have seen 50 ohms, 100 ohms, and two 50 ohm
>s in
>> parallel.. ! Is there a valid reason for using any particular value ??
> over
>> the years it seems that 50 ohms was the usual value, but today I found
> in
>> the amp I'm working on , a 100 ohm, two watt unit.
>> Any answers out there ??? thanks !
>> carl / kz5ca
>
>A politically correct answer would say that each amplifier needs its
>own suppressor, most likely you find in amplifiers all sort of
>suppressors or no suppressor at all.
>
** The AL-1500 (1, 8877) is the only HF amplifier I know of that has no
vhf suppressor. [Figure 24.1 on my Web site]
>Often suppressors are unavoidable, but not only an effective solution
>exists, there are more, so a cut and try products (something that works
>with something that is available) is used with old glass tubes or
>anyway with tubes that have big feedback.
>
>More than often suppressors are instead "included" as something that
>people is accustomed to find out but not really needed, the amplifier
>would be inherently stable at the frequency in use, with or without
>suppressors.
** In HF g-g, the problem is not stability at the frequency in use,
it's stability at the unavoidable vhf anode-resonance between the tube
and the Tune-C.
>
cheers, Mauri
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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