Radio shack Kit Question on transformer

[Ken]

Hello,

I have a kit that I bougfht from RAdio Shack , Here is a link of what I am
talking about. (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6019532542&indexURL=
)

I would just like to know what are on the transformers in this kit , There
are no part numbers and I need to replace that part.. The only information I
have is what is written on the board:
Output Transformer
900 8
----- -------
-
-----
-
----- ---------
Three legs going in and two out with these numbers on top.
Thank you for your help

Ken O

 

[Don Bowey]

Hello,

I have a kit that I bougfht from RAdio Shack , Here is a link of what I am
talking about. (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6019532542&indexURL=
)

I would just like to know what are on the transformers in this kit , There
are no part numbers and I need to replace that part.. The only information I
have is what is written on the board:
Output Transformer
900 8
----- -------
-
-----
-
----- ---------
Three legs going in and two out with these numbers on top.
Thank you for your help

Ken O

It is an audio output transformer, 900 Ohms to 8 Ohms, to connect to an 8
Ohm speaker. The 900 Ohm side may be center tapped.

Don

 

[DaveM]

Hello,

I have a kit that I bougfht from RAdio Shack , Here is a link of what I am
talking about. (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6019532542&indexURL=
)

I would just like to know what are on the transformers in this kit , There
are no part numbers and I need to replace that part.. The only information
I have is what is written on the board:
Output Transformer
900 8
----- -------
-
-----
-
----- ---------
Three legs going in and two out with these numbers on top.
Thank you for your help

Ken O

It's just a plain old audio output transformer. You already have the most
important specs: 900 ohms primary impedance with a center tap, 8 ohms
secondary impedance. Since this is a learning kit, I'm assuming that it is
low power, maybe a few hundred milliwatts.
I suggest one such as this from www.mouser.com as a close replacement:

Catalog # 42TU008
Primary 800 ohms CT
Secondary 8 CT
400 mw
$ 2.19 each

It's not an exact match, but, since it's an experimenter's kit, it's
insignificant. It will still work in the kit.
--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the address)

Never take a laxative and a sleeping pill at the same time!!

 

[Jasen Betts]

Hello,

I have a kit that I bougfht from RAdio Shack , Here is a link of what I am
talking about. (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6019532542&indexURL=
)

I would just like to know what are on the transformers in this kit , There
are no part numbers and I need to replace that part.. The only information I
have is what is written on the board:
Output Transformer
900 8
----- -------
-
-----
-
----- ---------
Three legs going in and two out with these numbers on top.
Thank you for your help

Ken O

looks like a transformer giving 900 ohms centre tapped on one side and 8
ohms on the other. these were popular in early transistorised products
(especially those that used 9V batteries)

if that's one of those "30 in one" "learn electronics" type kits
any audio transformer that's a "ballpark" match should work.

For example Jaycar cat# MM-2532 "1000 ohms CT to 8 ohms" (www.jaycar.com.au)
I expect there's a supplier nearer you with a similar product.

Bye.
Jasen

 

[ian.field1]

Hello,

I have a kit that I bougfht from RAdio Shack , Here is a link of what I am
talking about. (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6019532542&indexURL=
)

I would just like to know what are on the transformers in this kit , There
are no part numbers and I need to replace that part.. The only information I
have is what is written on the board:
Output Transformer
900 8
----- -------
-
-----
-
----- ---------
Three legs going in and two out with these numbers on top.
Thank you for your help

Ken O

Maplin do a pair of audio transformers - LT44 & LT77, one is a driver with
single primary/CT - secondary, the other is for O/P, CT - pri' & single LS
impedance secondary.

 

[UFO Joe]

I've got tons of those kits, going back 30 years.
I'm an amateur, but if I can help you...

Radio Shack used to sell them separately.

(We lost our Radio Shacks here in Canada - the Colonies - they were bought
out by some oversized American Crap company - Circuit City - now they're
into going for the big bucks
with Big Screen TVs and such, anyhow, forgive me, I digress.)

Radio Shack used to sell them as "Miniature Audio Transformers" if that is
any help.

The numbers on the board are the resistance, 900 Ohms in and 8 Ohms out
(Most speakers are 4-9 Ohms)

I really hope this helps you to find a suitable replacement.

 

[Ken]

if that's one of those "30 in one" "learn electronics" type kits
any audio transformer that's a "ballpark" match should work.

For example Jaycar cat# MM-2532 "1000 ohms CT to 8 ohms"
(www.jaycar.com.au)
I expect there's a supplier nearer you with a similar product.

Well you are right, Radio shack 200 in 1 kit.
supplied by a max of 9volts

Ken

And that you for all the help.

 

[Ken]

Because I do not have all the working parts. I decided to simulate this
circuit in pspice. I wanted to add this part the circuit. ( I only worked
with very simple circuit using a simulator,..capacitor resistor) there are
many to chosse from also , I wanted to add a transistor A733, there is none
in the simulator, how do I go about chooosing out of the 100 shown in the
simulator ??

thank you

Ken

 

[Jim Thompson]

Because I do not have all the working parts. I decided to simulate this
circuit in pspice. I wanted to add this part the circuit. ( I only worked
with very simple circuit using a simulator,..capacitor resistor) there are
many to chosse from also , I wanted to add a transistor A733, there is none
in the simulator, how do I go about chooosing out of the 100 shown in the
simulator ??

thank you

Ken

Get/Place Part Q2SA733

...Jim Thompson

 

[Robert Baer]

Hello,

I have a kit that I bougfht from RAdio Shack , Here is a link of what I am
talking about. (
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=6019532542&indexURL=
)

I would just like to know what are on the transformers in this kit , There
are no part numbers and I need to replace that part.. The only information I
have is what is written on the board:
Output Transformer
900 8
----- -------
-
-----
-
----- ---------
Three legs going in and two out with these numbers on top.
Thank you for your help

Ken O

Without looking, it is obvious to me; 900 ohm CT input and 8 ohm
output (to drive speaker or headphone) connects to the output push-pull
stage of an audio amplifier (or that part of a radio).

 

[Robert Baer]

Because I do not have all the working parts. I decided to simulate this
circuit in pspice. I wanted to add this part the circuit. ( I only worked
with very simple circuit using a simulator,..capacitor resistor) there are
many to chosse from also , I wanted to add a transistor A733, there is none
in the simulator, how do I go about chooosing out of the 100 shown in the
simulator ??

thank you

Ken

Pick any transistor of the same type (NPN or PNP) and similar use
(RF, audio or power).
No need to be picky for popcorn commodity stuff.

 

[safemale]

rat shack used to have them
i think
ham friend used them in the mic line of his home made rig blaster
sound card radio interface
safemale