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rob34 December 16th 03 05:41 PM

40673 Mosfets
 
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

Henry Kolesnik December 16th 03 11:26 PM

I think I remember the number from the dlate 1960s but can't recall what
their main use was, refreesher?
tnx
hank wd5jfr
"rob34" wrote in message
...
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob




Henry Kolesnik December 16th 03 11:26 PM

I think I remember the number from the dlate 1960s but can't recall what
their main use was, refreesher?
tnx
hank wd5jfr
"rob34" wrote in message
...
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob




JGBOYLES December 16th 03 11:42 PM

I think I remember the number from the dlate 1960s but can't recall what
their main use was


The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST

JGBOYLES December 16th 03 11:42 PM

I think I remember the number from the dlate 1960s but can't recall what
their main use was


The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST

Michael A. Terrell December 17th 03 12:05 AM

JGBOYLES wrote:

I think I remember the number from the dlate 1960s but can't recall what
their main use was


The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST


A lot of early solid state garage door openers used it, as well.
--
9 days!


Michael A. Terrell
Central Florida

Michael A. Terrell December 17th 03 12:05 AM

JGBOYLES wrote:

I think I remember the number from the dlate 1960s but can't recall what
their main use was


The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST


A lot of early solid state garage door openers used it, as well.
--
9 days!


Michael A. Terrell
Central Florida

rob34 December 17th 03 12:07 AM

rob34 wrote:

I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

For starters, Heathkit used them for their dip meters. There are a lot
of uses for this mosfet, and I am afraid they are scarce!! I have 20 of
them right now and I think I might be able to get more, but I am not
sure. If anyone is serious about this, I will sell this lot for $40.00 ,
so e-mail me. Rob WB8VWI

rob34 December 17th 03 12:07 AM

rob34 wrote:

I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

For starters, Heathkit used them for their dip meters. There are a lot
of uses for this mosfet, and I am afraid they are scarce!! I have 20 of
them right now and I think I might be able to get more, but I am not
sure. If anyone is serious about this, I will sell this lot for $40.00 ,
so e-mail me. Rob WB8VWI

rob34 December 17th 03 01:41 PM

rob34 wrote:
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

Thank`s for all the replies!! I have sold them and I am going to try to
scronge some more. MERRY CHRISTMAS TO ALL!!!!

rob34 December 17th 03 01:41 PM

rob34 wrote:
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

Thank`s for all the replies!! I have sold them and I am going to try to
scronge some more. MERRY CHRISTMAS TO ALL!!!!

Fred McKenzie December 17th 03 02:52 PM

I think I remember the number from the dlate 1960s but can't recall what
their main use was, refreesher?

Hank-

The RCA 40673 Dual Gate MOSFET was used as a low noise VHF RF Preamp in the
early 1970s. There were at least two preamp kits popular at the time, such as
the one from Topeka FM & Engineering. I used such a preamp on my Regency
HR-2A, supposedly improving the sensitivity from 0.35 uV to 0.2 uV. Of course
there was an increase in intermodulation interference that came with it!

While there are many such pieces of equipment still in use, there are newer
devices that can be used as a replacement for the 40673. An example (only
slightly newer) is the 3N201.

Today's FM rigs typically have better sensitivity even without an additional
preamplifier.

73, Fred, K4DII


Fred McKenzie December 17th 03 02:52 PM

I think I remember the number from the dlate 1960s but can't recall what
their main use was, refreesher?

Hank-

The RCA 40673 Dual Gate MOSFET was used as a low noise VHF RF Preamp in the
early 1970s. There were at least two preamp kits popular at the time, such as
the one from Topeka FM & Engineering. I used such a preamp on my Regency
HR-2A, supposedly improving the sensitivity from 0.35 uV to 0.2 uV. Of course
there was an increase in intermodulation interference that came with it!

While there are many such pieces of equipment still in use, there are newer
devices that can be used as a replacement for the 40673. An example (only
slightly newer) is the 3N201.

Today's FM rigs typically have better sensitivity even without an additional
preamplifier.

73, Fred, K4DII


J. Yazel December 17th 03 10:07 PM

On 16 Dec 2003 23:42:13 GMT, (JGBOYLES) wrote:

I think I remember the number from the dlate 1960s but can't recall what
their main use was

The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST

===========================

Some years ago, all of the radio magazines had many articles with
40673's. About every third article had at least one (slight
exaggeration).

Jack W8RAG



J. Yazel December 17th 03 10:07 PM

On 16 Dec 2003 23:42:13 GMT, (JGBOYLES) wrote:

I think I remember the number from the dlate 1960s but can't recall what
their main use was

The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST

===========================

Some years ago, all of the radio magazines had many articles with
40673's. About every third article had at least one (slight
exaggeration).

Jack W8RAG



Michael Black December 17th 03 10:34 PM

J. Yazel ) writes:
On 16 Dec 2003 23:42:13 GMT, (JGBOYLES) wrote:

I think I remember the number from the dlate 1960s but can't recall what
their main use was

The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST

===========================

Some years ago, all of the radio magazines had many articles with
40673's. About every third article had at least one (slight
exaggeration).

Jack W8RAG


That's not really a surprise. It's always been a constant that
a handful of parts are used in the magazines. By sticking to
a few parts, it guarantees that you will be able to get those
parts, since small companies that deal with the hobbyist will
carry those parts. And then in turn it guarantees that the
parts will be used.

Besides, many articles were traditionaly a variant on something
that had already been published. So someone looks in the magazines,
and picks parts (or even whole circuits) based on what they see,
and then write about it.

I've always tended to look at those common parts as a designator
for a generic category of something. So a 40673 is a dual gate
MOSFET, and likely some other similar part will fit the situation.
After all, if someone was going for extreme performance, it would
not be a common part.

Michael VE2BVW



Michael Black December 17th 03 10:34 PM

J. Yazel ) writes:
On 16 Dec 2003 23:42:13 GMT, (JGBOYLES) wrote:

I think I remember the number from the dlate 1960s but can't recall what
their main use was

The 40673 as I recall was a dual gate FET. Used in mixers and other stuff
dual gates were used. They were in a small metal package (TO-??) with 4 leads.
I think I remember their orginal application was CB xcvrs.
73 Gary N4AST

===========================

Some years ago, all of the radio magazines had many articles with
40673's. About every third article had at least one (slight
exaggeration).

Jack W8RAG


That's not really a surprise. It's always been a constant that
a handful of parts are used in the magazines. By sticking to
a few parts, it guarantees that you will be able to get those
parts, since small companies that deal with the hobbyist will
carry those parts. And then in turn it guarantees that the
parts will be used.

Besides, many articles were traditionaly a variant on something
that had already been published. So someone looks in the magazines,
and picks parts (or even whole circuits) based on what they see,
and then write about it.

I've always tended to look at those common parts as a designator
for a generic category of something. So a 40673 is a dual gate
MOSFET, and likely some other similar part will fit the situation.
After all, if someone was going for extreme performance, it would
not be a common part.

Michael VE2BVW



J. Yazel December 18th 03 09:15 PM


Some years ago, all of the radio magazines had many articles with
40673's. About every third article had at least one (slight
exaggeration).

Jack W8RAG


That's not really a surprise. It's always been a constant that
a handful of parts are used in the magazines. By sticking to
a few parts, it guarantees that you will be able to get those
parts, since small companies that deal with the hobbyist will
carry those parts. And then in turn it guarantees that the
parts will be used.

Besides, many articles were traditionaly a variant on something
that had already been published. So someone looks in the magazines,
and picks parts (or even whole circuits) based on what they see,
and then write about it.

I've always tended to look at those common parts as a designator
for a generic category of something. So a 40673 is a dual gate
MOSFET, and likely some other similar part will fit the situation.
After all, if someone was going for extreme performance, it would
not be a common part.

Michael VE2BVW
=====================================


That's a good idea except that few hams have the expertise to modify
a circuit for a different IC even if it is similar.

Jack W8RAG



J. Yazel December 18th 03 09:15 PM


Some years ago, all of the radio magazines had many articles with
40673's. About every third article had at least one (slight
exaggeration).

Jack W8RAG


That's not really a surprise. It's always been a constant that
a handful of parts are used in the magazines. By sticking to
a few parts, it guarantees that you will be able to get those
parts, since small companies that deal with the hobbyist will
carry those parts. And then in turn it guarantees that the
parts will be used.

Besides, many articles were traditionaly a variant on something
that had already been published. So someone looks in the magazines,
and picks parts (or even whole circuits) based on what they see,
and then write about it.

I've always tended to look at those common parts as a designator
for a generic category of something. So a 40673 is a dual gate
MOSFET, and likely some other similar part will fit the situation.
After all, if someone was going for extreme performance, it would
not be a common part.

Michael VE2BVW
=====================================


That's a good idea except that few hams have the expertise to modify
a circuit for a different IC even if it is similar.

Jack W8RAG



Eddie Haskel December 19th 03 02:18 AM

*Heathkit* used a ****load of them in EVERYTHING they made. They were in
the 2 meter radios as a mixer and front end, even in the TVM's
(Transistorized Volt Meters). The early solidstate "VTVM" (I know..they had
tubes in them) but Heathkit had a solidstate one and they used it as a meter
amplifier...Eddie
"rob34" wrote in message
...
rob34 wrote:
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

Thank`s for all the replies!! I have sold them and I am going to try to
scronge some more. MERRY CHRISTMAS TO ALL!!!!




Eddie Haskel December 19th 03 02:18 AM

*Heathkit* used a ****load of them in EVERYTHING they made. They were in
the 2 meter radios as a mixer and front end, even in the TVM's
(Transistorized Volt Meters). The early solidstate "VTVM" (I know..they had
tubes in them) but Heathkit had a solidstate one and they used it as a meter
amplifier...Eddie
"rob34" wrote in message
...
rob34 wrote:
I have a small quantity of RCA 40673 mosfets for anyone interested. I
will sell them for $2.50 each. These are NOS and I am selling them at
half the market value. If you get them through NTE they are over $11.00
or you get them through Dan`s small parts (if he has any) at$5.00 each.
Thanks, Rob

Thank`s for all the replies!! I have sold them and I am going to try to
scronge some more. MERRY CHRISTMAS TO ALL!!!!




Bruce Kizerian December 19th 03 02:49 PM

If you must replace a defective 40673 in an existing design this is a
good deal. However, these parts are dated and not that great by modern
standards. You can buy much better (though only in SMT) parts which
are still in production--such as the BF998--for a few cents each.

So, for replacement, yes, but why anyone would use them in a new
design or an adaptation of an old design is a mystery...but of course,
tubes still seem to attract some folks, too...

Bruce kk7zz
www.elmerdude.com

Bruce Kizerian December 19th 03 02:49 PM

If you must replace a defective 40673 in an existing design this is a
good deal. However, these parts are dated and not that great by modern
standards. You can buy much better (though only in SMT) parts which
are still in production--such as the BF998--for a few cents each.

So, for replacement, yes, but why anyone would use them in a new
design or an adaptation of an old design is a mystery...but of course,
tubes still seem to attract some folks, too...

Bruce kk7zz
www.elmerdude.com


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