Universal Tiger

Come on in, Tiger lovers.

Here at the Tiger-Twister we're slashing Tiger in half.
Give us an offer on our vast selection of Tigers, this is a Tiger blow-out allright.
We got white Tiger, black Tiger, spanish Tiger, yellow Tiger.
We got hot Tiger, cold Tiger, we got wet Tiger, we got smelly Tiger.
We got hairy Tiger, bloody Tiger, we even got snappin Tiger.
We got silk Tiger, velvet Tiger, nauga-hyde Tiger.
Come on, you want Tiger.
If we don't have it, you don't want it
Come on in, Tiger lovers!
 
DomLeBel said:
Allen,
many many moons ago, i built the plastic tiger and could not source the SS1122/1123. I got a hold of some people at Motorola and they told me that these were special marked for SWTP. They told me to use MM3007 and MM4007. When you look at the amplifiers that Dan Meyers designed, the MM3005 and MM4005 are showing up. These are a lower breakdown voltage of the same transistors.
Dominique


Dominique,

Been quite a while since I've checked the thread obviously. I haven't broke out the tiger since then. Hope to put it on the bench soon.
Thanks for the info on the SS1122/1123's.
Have you used the MM3005/4005? If so, how'd they work out?
I recently stumbled on a list of articles from Audio amateur back in 74. I'll try my local library to see if it's available for copying. Looks like it has some upgrade info for the Tigers in it. (AUDIO AMATEUR 1/1974 [Oct 1974] (v.5#1) pg. 20).
One of these days I hope to have a pair up and running again-mostly for nostalgia but I did enjoy the sound when they were paired with my old Mk C-22 and a decent turntable.

Allen
 
Allen,
I can vouch that the 2N5416\3440 works for the SS1122\1123. I rebuilt a pair of Tiger .01s a couple years ago. They still run the mids in my tri-amped system. I also used MJ15015\15016 outputs. I have a small stash of original 40409 and 40410 drivers, and most of an unbuilt "Brute 70" Amp from the late 60's. I added the small caps as per Jan's schematic. Any $50 chipamp will far surpass it, but when you get to the age you can remember them new, you can't hear anyway......

Bob G.
 
Bob,

I'm now shopping for a newer pair of eardrums with improved frequency response. I'm guessing I'm now about 6 db down at 12khz but seem to be ok in the 25 hz range.

Let me know what chipamps you've had good results with. I've wanted to experiment with them but never got around to it.

Allen
 
My Universal Tiger experience

I built four UTs in the 1974 time frame. By then, it was a well known fact that the original UT circuit overloaded its output stage bias resistors, which were made from carbon film resistors, which of course are unstable. The output bias drifted, and then the output stages failed.

I redesigned the circuit to increase the power rating on these parts. I changed the PC board artwork to accommodate the power resistors, but otherwise followed the original circuit.

One other modification I stumbled on, and that was the mounting of the thermal feedback diodes on the heatsinks. On two of the four channels I used the common diode clips, made from sheet metal. On the other two channels, I ran out of diode clips, so I drilled holes in the heatsinks and press-fit the diodes. This change was critical to thermal stability. I could adjust the output bias to optimum levels in the press-fit channels, but could never do that in the clip-mounted channels, because those channels would blow their DC fuses at high volumes.

I still have that four-channel UT, and it still works. There has never been an AC stability problem. However, I could imagine drifting DC bias causing AC instabilities.
 
About 30 years ago, I bought two Tiger boards with output heatsinks and transistors that were the original kits from a garage sale. The price was $10, IIRC, to my excitement. I still remember clearly the table sitting outside on that road not far from here. There were the kits along with the 1970 Popular Electronics issue containing the pertinent article by Dan Meyers. I also recall that the numbers printed on the MJ802/MJ4502 aluminum transistors were very worn. :)

I tinkered with the amps for hours on end and can't really recall much trouble with oscillation as checked with my tube oscilloscope. I definitely saw some approximately 5Vp-p oscillation kick in when the output voltage approached the one of the power supply rails (The positive one?) in some tinkered versions. I knew little about layout and compensation at the time, other than what was printed in the article. Yet studying the article as well as tinkering with the amps was how I really obtained a somewhat decent understanding of transistor theory.

I replaced the output transistors with steel ones most certainly because I blew the aluminum ones which the original owner had managed to nurse so well.

I eventually sold the amp to my brother with a microwave oven fan cooling the heatsinks and with MJ2905/2N3055 output transistors. I had the power supply cranked up to about +/-55V (no load) for a long time before I revamped it to how it was when I sold it. Then it ran off of the stock voltage, again.

As a side note, I once purchased some RCA 2N3055 which I employed as ignition point savers for my car ignition system. They broke down at 120V. I know because the coil flyback voltage would square off at that voltage level. They lasted for years of driving without failure. I was always ready to remove it if the car were to stall due to it failing, but it always worked even after I sold the car to a friend. It was still in there, I guess when the engine finally threw a connecting rod. He had gotten in touch with me too help him diagnose the problem, and when we parked the clattering car for the last time, I guess it was still in use.
 
Anyone have a Tiger MK II schematic?

Reading this thread reminded me that I still have 3 (of 4) Universal
Tiger MK II amps. One went up in smoke years ago, under conditions already described in this thread.

I cannot find my copy of the schematic, or anywhere else in DIYAudio forums, or elsewhere on the Web.

Does anyone have a schematic that they might share?
 
There are three versions of the Tiger (not counting the Tiger .01) that I am aware of.

The Tiger

http://www.swtpc.com/mholley/PopularElectronics/Jul1969/PE_Jul_1969_pg52.jpg

The Super Tiger/Universal Tiger/Universal Tiger II

http://www.swtpc.com/mholley/PopularElectronics/Oct1970/PE_Oct_1970_pg32.jpg

And the Tiger 'B'

This had the Tiger .01 front end (without the CCS) with the Super Tiger output stage ( a dual, the .01 was a triple).

http://www.swtpc.com/mholley/Catalog1973b/Page4.jpg

http://www.swtpc.com/mholley/Catalog1975b/Page4.jpg
 
There are three versions of the Tiger (not counting the Tiger .01) that I am aware of.

The Tiger

http://www.swtpc.com/mholley/PopularElectronics/Jul1969/PE_Jul_1969_pg52.jpg

The Super Tiger/Universal Tiger/Universal Tiger II

http://www.swtpc.com/mholley/PopularElectronics/Oct1970/PE_Oct_1970_pg32.jpg

And the Tiger 'B'

This had the Tiger .01 front end (without the CCS) with the Super Tiger output stage ( a dual, the .01 was a triple).

http://www.swtpc.com/mholley/Catalog1973b/Page4.jpg

http://www.swtpc.com/mholley/Catalog1975b/Page4.jpg

I am looking for the Universal Tiger MK II, as listed in http://www.swtpc.com/mholley/Catalog1973b/Page4.jpg. This one has 2 extra transistors (Q10 and Q11) which clamp the output transistors Q7 and Q8 under overload conditions.
 
FWIW, I've been running a scratch built unprotected Tiger for about 30 years now. Though I've blown it up several times, it's never been with music, only on the test bench. It can take all sorts of abuse, but not high amplitude high frequency drive. The output stage can't turn off, shorts out the power supply, exceeds the SOA and the smoking chain reaction begins.
 
I am looking for the Universal Tiger MK II, as listed in http://www.swtpc.com/mholley/Catalog1973b/Page4.jpg. This one has 2 extra transistors (Q10 and Q11) which clamp the output transistors Q7 and Q8 under overload conditions.

Hi, djk's description above of the different models is not quite right. You are correct that there is an early Universal Tiger without output protection, and a later version with output protection and some higher wattage resistors, I believe that they might have used cheaper - lower power output devices since the protection made this possible. I have one here and it has different outputs than the earlier version. I'm not sure if I've ever seen a schematic for the version with protection, actually it might have been reprinted in the Audio Amature article.
I wrote this a few posts back in this thread:
http://www.diyaudio.com/forums/solid-state/41926-universal-tiger-10.html#post597850

It would be fairly easy to mark up a schematic of the early Universal Tiger to show the output protection.

This is the early Universal Tiger, the later version - MKII just added output protection
and was built on the same chassis:
http://www.swtpc.com/mholley/PopularElectronics/Oct1970/PE_Oct_1970_pg32.jpg

Picture of the Universal Tiger MKII, the early Universal Tiger looked the same - some did
not have a pot for bias control:
http://www.swtpc.com/mholley/Catalog1973b/Page4.jpg

This is the Tiger .01 and was a completely new revision:
http://www.swtpc.com/mholley/RadioElectronics/Apr1973/RE_Apr_1973_pg68.jpg
 
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