Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

Thanks for the help

Skip..

Skip wrote:

Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

Thanks for the help

Skip..

5 each 7.5 volt 10 watt zeners in series might work. Or you might
build a power transistor circuit that current amplifies a small 35
volt zener. It all depends on the details of the circuit. That is
one hell of a bias zener.

--
John Popelish

Skip wrote:
Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

A simple shunt regulator using a TL431 and a pass transistor will give
adjustable voltage and better regulation than a large zener diode, and
is actually cheaper.

There's a lot of information on my website, at:
http://www.ifwtech.co.uk/g3sek/boards [some commercial content]


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'

or an LM317HVT with PASS transistor


"Ian White, G3SEK" wrote in message
...
Skip wrote:
Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

A simple shunt regulator using a TL431 and a pass transistor will give
adjustable voltage and better regulation than a large zener diode, and
is actually cheaper.

There's a lot of information on my website, at:
http://www.ifwtech.co.uk/g3sek/boards [some commercial content]


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'

or an LM317HVT with PASS transistor


"Ian White, G3SEK" wrote in message
...
Skip wrote:
Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

A simple shunt regulator using a TL431 and a pass transistor will give
adjustable voltage and better regulation than a large zener diode, and
is actually cheaper.

There's a lot of information on my website, at:
http://www.ifwtech.co.uk/g3sek/boards [some commercial content]


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'

Skip -

If you are build an amplifier .. I would use Ian's boards -
great protection, easy to assemble and takes your guess work out of older
designs

Greg
w9gb


"Ian White, G3SEK" wrote in message
...
Skip wrote:
Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

A simple shunt regulator using a TL431 and a pass transistor will give
adjustable voltage and better regulation than a large zener diode, and
is actually cheaper.

There's a lot of information on my website, at:
http://www.ifwtech.co.uk/g3sek/boards [some commercial content]


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'

Skip -

If you are build an amplifier .. I would use Ian's boards -
great protection, easy to assemble and takes your guess work out of older
designs

Greg
w9gb


"Ian White, G3SEK" wrote in message
...
Skip wrote:
Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

A simple shunt regulator using a TL431 and a pass transistor will give
adjustable voltage and better regulation than a large zener diode, and
is actually cheaper.

There's a lot of information on my website, at:
http://www.ifwtech.co.uk/g3sek/boards [some commercial content]


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'

Skip wrote:

Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

Thanks for the help

Skip..

5 each 7.5 volt 10 watt zeners in series might work. Or you might
build a power transistor circuit that current amplifies a small 35
volt zener. It all depends on the details of the circuit. That is
one hell of a bias zener.

--
John Popelish

Skip wrote:
Hello List,

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

A simple shunt regulator using a TL431 and a pass transistor will give
adjustable voltage and better regulation than a large zener diode, and
is actually cheaper.

There's a lot of information on my website, at:
http://www.ifwtech.co.uk/g3sek/boards [some commercial content]


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'

On Sun, 07 Dec 2003 18:01:57 +1300 Skip wrote:

I am looking for a source for a Zener Diode. I am building an HF
Amplifier using a GS-35b and the schematic I'm using to build the amp
calls for a 36v 50w zoner diode for bias. Here in New Zealand there
does not seem to be anyone with anythings close to what I need.

50 W stud mount Zeners used to be a standard product, but most
manufacturers dropped them about 20 years ago. I understand that they
were still available from someone for a long time, but they might be
completely unavailable by now.

Also, would it be possible to string a few lower volt watt zeners
together to come up with a close value to what is needed?

Sure, string 10 3.6V/5 W Zeners, that would work fine if you can get
3.6V, which seems unlikely.

A more reasonable solution would be to make your own regulator using a
low power Zener and a power transistor that can handle the power. You
can make either a shunt or series regulator this way.

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
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