On Nov 10, 2005, at 2:30 PM, Jerry Muller wrote:
> Is your glitch resistor a wire wound resistor? Your glitch resistor
> needs to
> be able to handle the full supply voltage for however long it takes to
> discharge the filter caps. Typically this isn't a long time and the
> wattage
> rating of the resistor can probably handle it. The key specification
> here is
> that the resistor needs to be able to handle the full supply voltage
> for a
> few milliseconds. Wire wound resistors don't cut it. They blow when a
> glitch occurs
An Ohmite 10 to 15 ohm 10w, glass-coated non-adjustable WW resistor
will safely discharge c. 100J.
> .
>
> Metal film or carbon comps are OK.
Carbon comps tend to explode in glitch service. Metal-film resistors
are okay if their J-rating is adequate for the filter-C in use.
>
> I haven't started my GS35B amp yet, but I'm planning one for 70cm.
>
> 73 es gl,
>
> Jerry, K0TV
>
> ----- Original Message -----
> From: "Carlo Houben" <carlo.houben1@pandora.be>
> To: <Amps@contesting.com>
> Sent: Thursday, November 10, 2005 4:43 PM
> Subject: [Amps] gs35b on hf problem .
>
>
>> Hi , i am building a hf amp around a gs35b (new old stock ) in a GG
>> configuration
>> g3sek triodeboard for control .
>> HV 3300V no load .
>> The following is my problem :
>> 1/ My glitch resistor 33 ohm 17 w passed out by measuring zero
>> signal
>> anode current .
>> first it was 20Ma and after i put the bias voltage to around 29 V it
>> was
>> 100 Ma .
>> but after 3 times ptt the glitch resitor past out .
>> annyone an idea where i have to look for .
>> Thanks in advance .
>> 73
>> ON4BR
>>
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>
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>
Richard L. Measures, AG6K, 805.386.3734. www.somis.org
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