Radio shack Kit Question on transformer

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

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

Catalog # 42TU008 Primary 800 ohms CT Secondary 8 CT

It's not an exact match, but, since it's an experimenter's kit, it's insignificant. It will still work in the kit.

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.

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"

Bye. Jasen

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.

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

Ken

And that you for all the help.

Get/Place Part Q2SA733

...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

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).

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.