Very old pignose 7-100

[larwood.amps]

As i have already mentioned in a previous post, i have quite literally been blown away by this foray into solid state circuitry.
I cant thank you all enough for all the suggestions and schematics, it only leaves me to apply the brain to the technology and letting you all know the outcome.
Once again thanks to everybody.

Larwood.

[Borg54]

Larwood, if you get that pig up and flying again. There is a really cheap and easy mod for the Pignose. Almost everyone that I know has fallen in love with the thing at 1/2 battery life. The same Tone can be achieved with the wall-wart PS by taking and wrapping the dc cable around a ferrite core. Just keep wrapping until you have the tone that you?re after. The mojo is in the turns, I don't question why and how some things seem to work, they just do. Have Fun

Doug

[larwood.amps]

Thanks Doug,
I'll definitely try that, i have even thought of having an onboard wart so's there would always be a permanent power supply.
But at this moment in time i have arrived at the conclusion that the resistor that burnt out is the bleed resistor between the two 324 transistors, 1R-1W Carbon. Now i cant say that is the correct resistor , because although all the other resistors are original ( white insulation paint on the legs ) only 11 of the 18 resistors tie up with the schematic. I've searched the case for more clues as to the age, and where the 9v input is , is a stamped date, that looks very much like 14 APR 1978. Now the other schematic that was posted by Teemuk, shows an 8.2R resistor in the bleed off..
But most of all , until I've located the transistors i wont be going ahead with the rebuild in case there was a backwash of damage to the other components before the resistor burnt out.
As i said in other posts I'll keep everybody up with the progress as i go along. Because along with all the help I've received from the Forum WE CAN'T FAIL CAN WE.

[Cagey]

. There is a really cheap and easy mod for the Pignose. Almost everyone that I know has fallen in love with the thing at 1/2 battery life. The same Tone can be achieved with the wall-wart PS by taking and wrapping the dc cable around a ferrite core. Just keep wrapping until you have the tone that you?re after. The mojo is in the turns, I don't question why and how some things seem to work, they just do. Have Fun

Doug

Noob translation request: "wall-wart PS" - the AC adaptor? Ferrite core - a magnet or just iron? Thanks.

[Cagey]

Noob translation request: "wall-wart PS" - the AC adaptor? Ferrite core - a magnet or just iron? Thanks.

OK figured out the WW. I haven't seen this mentioned anywhere else. Does anyone else have another reference to this trick?

I found a "Dying battery simulator" - another way to achieve the same effect?

http://beavisaudio.com/Projects/DBS/

[pignose7]

Mybe this is a dead thread, but I have a pignose 7-100 that I bought in Japan in the early 90's. I just started using it again and was looking into the power situation as far as adapters and batteries go.
Just to confuse things, the Korg PS I used from Japan had a negative tip, positive ring. The shop sold me a little pigtail adapter with the 3.5mm plug on it that reversed the polarity. All seemed fine and at the time I did not know that the pigtail reversed the polarity. The amp worked so I never even thought about it. But if you take the amp apart a red wire is connected to the ring and a green wire is set up on the tip.
Go figure.
I have actually tried a US PS with positive tip, negative ring and used the same little pigtail with the pignose and it still worked.
So what gives?
Pretty simple really. You have to go with what the amp wiring says and I am going to have to assume that the red wire meant positive ring.
I am going to build a little external battery supply for NO HUM and longer playing time with the amp.
First post.

[kubitica]

Bumping this thread back to life

Hi
I don't know too much about electronics, but given the interest in the Pignose 7-10, I thought I'd mention that for a while I've been collecting and interpreting the various schematics, with a view to posting a schematic of a close-to-original (Silicon BJTs) version of the amp. This is almost complete, but I'm not quite sure about the driver and output transformers. The driver seems to be about 2:1 (about 1k:500CT ?). Some schematics show a resistance of about 70 ohms on the secondary, which suggests a 400 to 1k ohm secondary. The output transformer in older amps seems to be a step down (48:8 ohms ?), like the old push-pull Mullard-design radio amps (discussed above). However, I suspect that the more modern output devices (TIPs) could handle lower ratios (8:8) and together with the lower emitter resistors, would put out more power (e.g. the 5W claimed). With a 48:8 transformer, the maximum power achieved seems to be about 1.5 W (according to my spice simulations).

If anyone has details about the transformers (DC resistance or impedance, overall size, core size, path length) I would be very grateful to have it. If anyone has a dead pignose and is interested in selling it, I would also be interested.

Thanks

PS the emitter resistor varies in different schematics. This isn't surprising, given that the output trannies can be old, low-power Ge dvices (needing that 8.2 ohm resistor), or modern TIP41s (that seem to have a 2.7, 2.2 or 1 ohm resistor. 2.2 ohms seems a good compromise in my spice simulations.)

[davidw]

I have been fortunate enough to own a very early Pignose for the last 15years, handmade and with a branded serial number, made by the inventors Richard Edlund and Walter Kimbell, with their address and phone no. (at the time), and a hand written dedication to the artist concerned.
It is one of 500 or so that were handmade and given to various name guitar players and bands to promote their invention at the time.
My question is, does anyone know anything about these very early handmade Pignose amps, there is a reference on the internet to one of them, no.064, that was given to Keith Richards of the Rolling Stones, but little else. The one one I've got pre-dates no.064.

Any information would be most appreciated, DavidW.

[Enzo]

Did you CONTACT Pignose and ask if they have any historical notes?

[ReginaldBisquet]

I'm very curious to read more on the original part values for this amp. I have read many reviews on how the older (1970s) Pignose amps sound so much better than the current stock. When I was checking out the circuit board, I noticed that there were not a lot of parts involved... so I'm wondering if swapping out the parts for something else (what - I don't know) to achieve a "classic" Pignose sound.

Mine is from 1997 and has the Creation label on the board. To date, the only mod I've done is enable the rear output jack to power an extension cabinet (below):



Otherwise, I once replaced the stock speaker with a Jensen 5" MOD... sounded quite bad so I put the original back in.

[teemuk]

Did you CONTACT Pignose and ask if they have any historical notes?

I'm not even sure if they have any considering the company's history.

Here's some of my personal notes I have compiled from few sources:

Wayne L. Kimbell and Richard P. Edlund, partners from doing graphics and photography for the Rock & Roll trade in the very late 1960’s, came up with the idea of the Pignose mini amplifier when they saw a small, 5-watt Pacific Radio unit. The Pignose prototype was practically copied from an old radio circuit and housed inside a leather-covered cologne box. The prototype was handed to Richard’s friend Warren Zevon, who immediately fell in love with the little amplifier. Producer Steve Binder got interested and started to promote the amplifier by paying the patent attorneys and by providing sufficient funding to produce a small amount of the Pignose amplifiers. 65 Pignose 7-100 units were made and they were given to various famous musicians for promotional purposes.

The records show that the first patents for the Pignose design were filed in the early 1970’s. Two US patents were granted: One for ornamental design (Des. #231,537) and one for the feature to modify the tone and the amplifier’s response by opening or closing the amplifier’s hinged cabinet (#3,860,755).

About a year passed from crafting the original Pignose design, during which Richard moved away from LA to San Francisco. However, Wayne had persuaded Jimmy Guercio, the producer of the band Chicago, to fund the founding of Pignose Industries, Inc. In 1974, Richard moved back to LA, the company was founded and the re-designed version of the model 7-100 was put to production. The revised unit now featured metal corner protectors and a new design patent was granted (Des. #240,315). Howard Chatt's company Roadrunner Cases in Gardena, CA manufactured the hardwood pigskin covered cases and the company’s factory in Hong Kong manufactured the internal electronics. The final assembly was done in US and Martin Guitars handled the distribution.

In the mid 1970’s, after the success with model 7-100, Pignose introduced an ordinary AC-powered solid-state guitar amplifier, the model 7-3060 (known as “30/60”). These were OEM units designed and manufacturered by Patrick Quilter’s Quilter Sound Company, which later became QSC Audio. The same company also manufactured a bass amplifier titled Bass Forty for Pignose. It was based on the 7-3060 chassis.

In circa 1978 Pignose introduced the solid-state “60R Studio Reverb 112”, which was followed by the “150R Crossmix”. Paul Rivera’s Rivera R&D reputedly designed both units although they relied heavily on the original 7-3060 design as well. For example, the 150R circuit is very “QSC-inspired”, featuring the “grounded output” power amplifier similar to Patrick Quilter’s famous designs. The Crossmix 150 reputedly had a failure rate of about 90% and turned out to be a service nightmare for the company. 60R is supposedly a 7-3060 with added reverb feature and ProCo RAT style distortion circuit in the preamplifier. Paul Rivera Sr. is not very keen on talking about this model so likely it was even a bigger flop than the Crossmix. The production of these amplifiers continued at least to 1982 and they were revised a few times.

The control of the company was at some point given to Candace Fagan and in 1982 Pignose was sold to the Howard Chatt’s Roadrunner Cases. This started the downfall of the company. Howard got rid of the other amplifier models except the 7-100 and transferred the production completely into Hong Kong.

Today, Wayne’s Kimbell Design Labs produces graphics and marketing material for print, Internet and video media. Richard has been working on special effects production for Hollywood movies and has won many awards of those. His work is featured, for example, on the first three Star Wars films and in the Indiana Jones Raiders Of The Lost Ark movie.

At the time of writing, Pignose Industries is still under ownership of Howard Chatt and the company also produces the notorious Gorilla Amplifiers. In 1998 the Pignose product range expanded with the all-tube G40V, G60VR and B-100 guitar and bass amplifiers. Dennis Kager from Ampeg and Sundown fame designed the G40V, which was soon followed by lower power “Hog”-series G30V and G20V. All the amplifiers are manufactured in Hong Kong.

[mrascon1086]

HI ReginaldBisquet, I know this has been a while since you posted this, But do you still have the Color picture of the board on that 7-100?
I just received one and I opened it and alot of the wires are disconected. Just need to see what color wire goes where?

[ClassicRocker]

I have one of the early 70's models, originally bought in about '76 or '77 for me as a present. I had once completely fried the board by applying a high power source, (young and inexperienced) I ordered a new board shortly thereafter from the company I think it was called Pignose international, could be wrong about that. I have had this board in there ever since, I used to carry this little pignose with me everywhere. It has worked very well for all of these years, when the original speaker cone broke I put in a speaker from radio shack which worked fairly well, I thought I would make a great improvement and install an actual Celestion speaker, five inch just like the original with about the same size magnet, looked like almost an exact match, although this speaker is 8 Ohm. It took me years to figure out just how to reconnect the original connection for an adaptor. I did get it to work, but I started noticing after great sound at first, the whole thing starts to fade out almost completely until it cannot be heard or just barely even at full volume. I once again took out the board, removed the metal cover around the transformers I immediately found the transistor on the left side extremely hot to the touch, once it cools down it sounds ok again. Is this caused only by a faulty transistor and can I replace it with another germanium transistor, I have built several fuzz boxes with varying success with transistors from a local large electronics store. Are these PNP NPN transistors, I didn't see anything in any of the previous post stating what type they are, the transistors are the same as was mentioned earlier in this post, Two B324's, one B175 and one B172, I would to get any help on this I love this little amp.

[52 Bill]

Is this caused only by a faulty transistor and can I replace it with another germanium transistor, I have built several fuzz boxes with varying success with transistors from a local large electronics store. Are these PNP NPN transistors, I didn't see anything in any of the previous post stating what type they are, the transistors are the same as was mentioned earlier in this post, Two B324's, one B175 and one B172, I would to get any help on this I love this little amp.

I assume the transistor that gets hot is a B324? One of the outputs. It could just be a bad transistor or it could be a circuit problem. I'd replace the transistor as a first step. It is a germanium PNP, 2SB324.

[angelodp]

Pignose problems

Hi, old thread, new problem. I have a 7-100 model that passes signal but there is a lot of crackling and other noises. I cleaned thevolume pot but still have the problem. Any insights as to possible causes, seems like a grounding noise. I have the original power supply and it does the same thing under battery power.