[schoey2k]

Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny

[Serge Auckland]

schoey2k wrote:
Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny


If you could tell us what the kit was, we may be n a better position to
advise. I have many old Wireless World circuits which Hart sold
commercially, so may be able to provide the information you need.

S.

--
http://audiopages.googlepages.com

[schoey2k]

I'm afraid there are no specifics witten on the board, so i have no
idea what the specific kit was, all i know is that it's a power
amplifier and requires a 0-60V supply, would a photo of it help?

Danny

On 21 Apr, 16:18, Serge Auckland wrote:
schoey2k wrote:
Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny

If you could tell us what the kit was, we may be n a better position to
advise. I have many old Wireless World circuits which Hart sold
commercially, so may be able to provide the information you need.

S.

--http://audiopages.googlepages.com

[Serge Auckland]

schoey2k wrote:
I'm afraid there are no specifics witten on the board, so i have no
idea what the specific kit was, all i know is that it's a power
amplifier and requires a 0-60V supply, would a photo of it help?

Danny

On 21 Apr, 16:18, Serge Auckland wrote:
schoey2k wrote:
Hi
I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?
Danny
If you could tell us what the kit was, we may be n a better position to
advise. I have many old Wireless World circuits which Hart sold
commercially, so may be able to provide the information you need.

S.

--http://audiopages.googlepages.com


Photos of both sides of the board may well help, as I may be able to
identify it from there. With a single-ended 60 volt supply it could be
the Bailey 30 watt amp, which was designed with either +-30 volt or +60
volt supplies, but then again, it could be something else......

S.

--
http://audiopages.googlepages.com

[schoey2k]

On 21 Apr, 17:41, Serge Auckland wrote:
schoey2k wrote:
I'm afraid there are no specifics witten on the board, so i have no
idea what the specific kit was, all i know is that it's a power
amplifier and requires a 0-60V supply, would a photo of it help?

Danny

On 21 Apr, 16:18, Serge Auckland wrote:
schoey2k wrote:
Hi
I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?
Danny
If you could tell us what the kit was, we may be n a better position to
advise. I have many old Wireless World circuits which Hart sold
commercially, so may be able to provide the information you need.

S.

--http://audiopages.googlepages.com

Photos of both sides of the board may well help, as I may be able to
identify it from there. With a single-ended 60 volt supply it could be
the Bailey 30 watt amp, which was designed with either +-30 volt or +60
volt supplies, but then again, it could be something else......

S.

--http://audiopages.googlepages.com- Hide quoted text -

- Show quoted text -

I'm having a few problems trying to get the photos to somewhere i can
link to them, but a Bailey amp rings quite a few bells,

[Serge Auckland]

schoey2k wrote:
On 21 Apr, 17:41, Serge Auckland wrote:
schoey2k wrote:
I'm afraid there are no specifics witten on the board, so i have no
idea what the specific kit was, all i know is that it's a power
amplifier and requires a 0-60V supply, would a photo of it help?
Danny
On 21 Apr, 16:18, Serge Auckland wrote:
schoey2k wrote:
Hi
I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?
Danny
If you could tell us what the kit was, we may be n a better position to
advise. I have many old Wireless World circuits which Hart sold
commercially, so may be able to provide the information you need.
S.
--http://audiopages.googlepages.com
Photos of both sides of the board may well help, as I may be able to
identify it from there. With a single-ended 60 volt supply it could be
the Bailey 30 watt amp, which was designed with either +-30 volt or +60
volt supplies, but then again, it could be something else......

S.

--http://audiopages.googlepages.com- Hide quoted text -

- Show quoted text -

I'm having a few problems trying to get the photos to somewhere i can
link to them, but a Bailey amp rings quite a few bells,

You can email them to me directly, and I can post them on my web site below.

S.

--
http://audiopages.googlepages.com

[none]

schoey2k wrote:
Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny


About 40 years ago, i remember of Hart amplifier kits being
sold in the Netherlands. they were a 1:1 copy of the Quad 303
although the mechanical construction may probably be different.

http://richardbrice.net/quad33&303.htm

Andre

[schoey2k]

On 22 Apr, 21:36, none ""andre\"@(none)" wrote:
schoey2k wrote:
Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny

About 40 years ago, i remember of Hart amplifier kits being
sold in the Netherlands. they were a 1:1 copy of the Quad 303
although the mechanical construction may probably be different.

http://richardbrice.net/quad33&303.htm

Andre

Thanks for that, as far as i can see topology of the PCB circuit is
preety much the same as the quad 303 topology, there are a few little
differences, like a couple of the output transistors are connected
directly to the power rail rather than via a resistor, but i'd be
confident to get any info i need about the PCB circuit off the quad
schematic

Danny

[schoey2k]

On 22 Apr, 21:36, none ""andre\"@(none)" wrote:
schoey2k wrote:
Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny

About 40 years ago, i remember of Hart amplifier kits being
sold in the Netherlands. they were a 1:1 copy of the Quad 303
although the mechanical construction may probably be different.

http://richardbrice.net/quad33&303.htm

Andre

Thanks Andre, from the looks of things, the PCBs circuit topology is
pretty much the same as the 303's, particularly the output stage and
the bias setting, i've yet to look in enough detail how different any
of the resistor values are, but i'd be inclined to trust the 303
circuit for transistor types, tell me if i'm very wrong,

Danny

[schoey2k]

On 25 Apr, 19:09, schoey2k wrote:
On 22 Apr, 21:36, none ""andre\"@(none)" wrote:





schoey2k wrote:
Hi

I have recently came accross an amplifier built from a kit (possibly
40 years ago), lacking it's off-board transistors, which has "Hart
Electronics" etched onto the board, and also i have a box of
components with a return address to Hart Electronics of Manchester,
does anyone know if this company still exists in any capacity such
that i could possibly find out what type of transistors to use?

Danny

About 40 years ago, i remember of Hart amplifier kits being
sold in the Netherlands. they were a 1:1 copy of the Quad 303
although the mechanical construction may probably be different.

http://richardbrice.net/quad33&303.htm

Andre

Thanks Andre, from the looks of things, the PCBs circuit topology is
pretty much the same as the 303's, particularly the output stage and
the bias setting, i've yet to look in enough detail how different any
of the resistor values are, but i'd be inclined to trust the 303
circuit for transistor types, tell me if i'm very wrong,

Danny- Hide quoted text -

- Show quoted text -

Sorry about the double message, i assumed the first one had decided
not post when it hadn't appeared in a couple of days