HH TPA series Power Amplifiers.

[Trevor]

Thanks for that, it's as I remember.

[Jeff D**]

Hi Trevor,

Just wizzing back to your earlier observations about the TPA 100 (post 46), do you have any observations on the music quality of the earlier amp?

Regards,
Jeff

[Kala_12]

Hi Jeff,

Attached a copy of the circuit diagram of the TPA 100D as requested.
I'm a bit confused. The reference to Trevor's post #46, about a TPA 100, from what I understand, it can't be a TPA100 as there is no driver transformer and it can't a TPA 100D as there are only two output transistors.

Stuart.

[Kala_12]

Oops, forgot to attach the file. Sorry.
It's on the other post, what am I thinking.
As regard to the output load, the booklet states "the amplifier will deliver it's full rated power direct into 15 ohms, and will deliver 170 watts rms into 7.5 ohms.
Stuart

[teetoon]

Hi Stuart, the diagram in post 46 is the TPA 100. If you look at the bottom lefthand side you can see the coils of the driver transformer. Trevor did appologise for the drawing but it's all there. No one has come up with an original drawing for this amp so Trevor traced it all out whilst working on it.

He never did report back on the musical quality of the amps, likewise I never did anymore to the 100 that I kept. There's always something else to do.
My TPA amps are now in a lock up after moving house last year.

[Jeff D**]

Hi Stuart, sorry I haven't been back before. As teetoon says the original 100 is a quite different circuit and I thought it should sound good which is why I asked for an update on performance.

Perhaps Trevor will be along soon.

[Kala_12]

Dave,

I have been following this thread about HH TPA100D and TPA100 power amplifiers. This reminds me of a two (or three) part article in Practical Wireless about a power amplifier which started as a single ended transistor amp which then progressed to using a trifilar wound transformer to drive a pair of TO3 PNP power transistors (OC35 if I remember correctly). These two transistors drove the loudspeaker directly. This appears to be a similar idea to the above mentioned TPA100. I wonder if this rings a bell and if it does, would you be able to let me have a copy of the article please?

Thank you in anticipation,
Stuart

[Kala_12]

Hi all,
I have the answer thanks to Keith.
For anyone interested, this is the link Keith gave me.

https://www.vintage-radio.net/forum/s...ad.php?t=62753

I used the power amplifier as a built in amp in an early disco console, but then invested in the two TPA 100Ds.
Stuart

[dragonser]

Hi,
I've just checked and the only circuit I have got is for the TPA 50 which doesn't have any driver transformers....
regards Peter B

[Aub]

Hi all,

As a follow up to my post #39, in this thread, I've evantually got round to finding the HH marketing material from 1976. ( it only took me 4 years ) If you look carefully, you can see where the dealer wrote the prices on with a pen.

Of course, they are later amps than in the original post but I hope you find them interesting non the less.

Cheers

Aub

[Aub]

And also the PA systems:-

[teetoon]

Hi Aub. That's quite interesting to see the prices. I also didn't realise that the MA 100 was rated at 120 watts. They always sounded loud anyway although not as nice sounding as the TPA range.

Shame that Trevor never reported back with his thoughts on the sound of the TPA 100's. Probably got too many other amps to play with .

I've not used any of mine in the last 3 years after moving but I have got my own storage now so no excuse! I have been thinking of selling some to make room for more recent acquisitions. I still like the old amps as they are so easy to repair. No SMT or SMPS to bother with.

David.

[kamran yousaf]

Respected Sir,

Can you please share its parts details as well. I like this amp and I wants to make it so need maximum detail like schematic PSB snap shot , layout etc Thanks.

Respected All,

I like this amp a lot so please share its complete parts list like schematic, PCB layout , snap shot and other details Thanks.

Respected Sir,

Can you please share its Schematic with the parts details Thanks.

[teetoon]

Hi Kamran, are you asking about the early TPA 100 with interstage transformer?
If so you will see in this thread that very little information has been found.
We have a hand drawn schematic that Trevor did but nothing else.
I will try to dig out my remaining amp and get a better picture of the board for you tomorrow.

David.

[teetoon]

Hello again. Here are some pics of the circuit board as requested by Kamran.
This is the TPA 100 not the 100 D which is a completely different design.

[teetoon]

Just a few more.
Hope these are useful.

[kamran yousaf]

Respected All,
Can any one share any or complete details of these Amps e.g.

Schematic diagram
Snap shot of front view of circuit
Snap shot of back view of circuit

I need just one more favour, please upload an image of the back side of PCB (PCB Layout) of amp MA100 MKIII

I shall be really very thankful to you in this regard .

Last Pic is of TPA 100D ?

[teetoon]

Hi Kamran. I've taken a few pics of the MA 100 board. I'm not sure about a MK III but this is the board fitted as standard to the later MA's using 2N3773 output devices.
Hope this helps.
That last pic above was the TPA 100 with interstage transformer.

David.

[kamran yousaf]

Thank you so much dear Mr. teetoon. I was waiting for you reply and its 12:45am in Pakistan. Is it your original name Sir teetoon.

Your and my story is almost same e.g. I start watching electronics my father in my childhood, after that I worked in electronics repairing shop for 5,6 years parallel to my studies up to graduation.

Did you recognize snapshot of my local TPA100 or 100D which was labelled like Lucky Electronics on the back of PCB ?

Just ignore the variable near the input, then what is model / name of this TPA amp

[kamran yousaf]

Originally Posted by teetoon

Hi Terry, from the amps I've had, all the TPA 100 D's have a pair of 2N3440 transistors on the input. The 50 D's and 25 D's have a 741.

Sir,
Please see the uploaded image and firstly this was uploaded by you
This was posted by you what is the name and other details of this TPA ?