| Saving a Frankie [message #14816] |
Sat, 04 December 2010 17:11  |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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I just saved a Frankie from a junk heap somewhere and I'm in need of info to somewhat restore it. This is what I do know, its a model 695PA, it had 6 power transistors mounted on the back panel which are missing, there is 3 more 1/8" holes on the back where something was mounted and a 1" hole where maybe a 110 volt outlet would be mounted. I dont see a driver board like the B series amps have mounted to the back. Theres a 2" X 5" board, with the reverb wires soldered in, mounted to the bottom on one end of the chassis. Theres another board mounted on the bottom of the chassis just behind the the front panel. All the knobs, fuses and power switch are present and look to be original and conected. There are 2 Mallory electrolytic capacitors (1=50v and the other 75v. along side mounted to the bottom of the chassis is a plate with looks to be 4 diodes. Theres a red and a gray wire twisted together coming from the curcuit board along the front panel laying loose unconected. Theres a gray wire coming from the side board with the reverb wires also loose and unconected. Where do we start? Thanks Steve
Steve C
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| Re: Saving a Frankie [message #14820 is a reply to message #14816] |
Mon, 06 December 2010 07:15  |
stevem
Messages: 4774
Registered: June 2004
Location: NY
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Senior Member |
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I will anwser your last question first, and this is not a smart ass reply.
YOU NEED TO GET ANOTHER AMP!!!
Your model 695 PA HEAD in regards to holes on the rear panel is missing.
1) The four output transistors.
2) the 2 similar transistors to the outputs that are part of the power supply voltage regulator circuit.
3) the whole driver board/regulator circuit.
4) the output driver/phase inverter transformer.
5) And I guess the four 10 watt output transistor emitther resistors and coupling caps.
It would also seem from your comments that your amp is missing the power transformer.
All the items you need other than the output transistors,power transformer and emitter resistors can only be had out of another Frank model head.
I guess if you had a real burning desire and the time for a long project you could swap in the power supply/driver and output stage from a A or B serise head which would be easyer and cheaper to find.
In rethinking what I just posted your best,cheapest and fastest bet would be to install one of the many 100 watt IC type output packs that can be had and a power supply to run it.
[Updated on: Mon, 06 December 2010 07:19] Report message to a moderator |
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| Re: Saving a Frankie [message #14823 is a reply to message #14820] |
Mon, 06 December 2010 09:21 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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I've collected plenty of parts over the years. The info I need is, What is the two wires (Red and Gray twisted together) coming from the pre amp section along the front panel? What is the gray wire coming from the reverb section? I would assume that the gray wires are the signal output and the red wire would be the positive supply for the pre amp section itself. I NEED A SCHEMATIC FOR THIS AMP so I can get the proper supply voltages. I have several "KUSTOM" complete power sections to put in there and that would be my intention at this point because of the missing transformers. What is the pre amps operating voltage, you suggested the B model so is that going to be 8 volts? If you have the schematics for this could you scan and email them to me at cassent5150@hotmail.com or forward this message to someone that has schematics so I can get a copy? Thanks soooooo Much Steve C
Steve C
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| Re: Saving a Frankie [message #14826 is a reply to message #14816] |
Mon, 06 December 2010 12:33 |
chicagobill
Messages: 2006
Registered: April 2003
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Senior Member |
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Is this the chassis that was on eBay?
Steve is right there is little hope of restoring this head with so many pieces missing. I guess that you could come up with some sort of power supply and a power amp and stick it in there and make it work as an amp, but that's your call.
The preamp needs +24vdc. The red wire is the power supply line and the grey wires are the signal outs from the preamps. The board right behind the front panel is the preamp circuit and the small board on the left side is the reverb circuit. The hole on the back of the chassis is a relief hole where the back of the 1/4" speaker jack used to fit. There was originally a black perforated metal panel that covered the power transistors and it also held the ac cord strain relief and the speaker out jack.
I will email you the schematic for this amp later today.
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| Re: Saving a Frankie [message #14827 is a reply to message #14826] |
Mon, 06 December 2010 14:35 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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Thanks chicagobill that would be fantastic. My intent is to save the cosmetics of the amp and retain the appearance while still maintaining the "Kustom Vintage Sound". If the preamp section with the reverb section can be used I will just install one of the power sections from another Kustom. My first option is a Module unit that I believe to be from an extention cabinet for a K250. It has a 5065 board so I have to decide where to get the supply voltage for the preamps. Where as the PC703 or 900 have thier own regulated supply, I'm thinking power from the caps via resistored to supply voltage like it does in the K250 and K150's. Is this the way to go? I'd rather part out one of the 2 module units I have than a amp head if you know what I mean. Steve C
Steve C
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| Re: Saving a Frankie [message #14837 is a reply to message #14834] |
Tue, 07 December 2010 21:27 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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Wow, thats great info, but its like way over my head!!! Lets see now if I understand any of that. I would use the module transformer and curcuitry as the output portion only and hook the gray wires to the input of the 5065 board. Now powering the preamp section with a seperate transformer, lets say the hammond one you mentioned, I would mount a 3 amp rectifier bridge (I'm assuming that this is to change an AC output from the transformer to a pulsating DC current) and the output of the rectifier bridge would be the Plus and minus voltage hooking to the two 10,000 uf fifty volt caps. I haven't a clue where the two 24 volt zenear diodes would go. You said hook one to each leg of the preamp supply. Lets say the plus being the red wire, the zenear would go from that leg to ground? Then there's another problem, (no green minus voltage wire coming from the preamps on this frankie) it looks as though the preamp uses the chassis for ground. Would you be hooking the other zenear from the minus leg off of the cap to ground? I'm just a beginner at this type of venture. Steve C
PS Thanks for all the help you give me, I learn so much from all of you that share the wealth of knowledge that ya'll have.
Steve C
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| Re: Saving a Frankie [message #14841 is a reply to message #14816] |
Wed, 08 December 2010 11:56 |
chicagobill
Messages: 2006
Registered: April 2003
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Senior Member |
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If you are planning on using a PC5065 board for the output, you will need a power transformer, diode bridge and two filter caps to create the + and - 40vdc needed to power the output amp.
You can then take the feed from the +40 volt supply and send it through a resistor and into a 24 volt Zener diode to power the preamp board.
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| Re: Saving a Frankie [message #14842 is a reply to message #14841] |
Wed, 08 December 2010 23:29 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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I bought that frankie chassis on ebay. Hope it has everything I need. I could see it had a tranny and reverb tank. We'll see when I get it. I still may use the spare frankie chassis to put that module unit into. The module unit has everything it needs to operate. I just have to remove it from its case and mount it inside the frankie chassis. Steve C
Steve C
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| Re: Saving a Frankie [message #14844 is a reply to message #14843] |
Thu, 09 December 2010 09:51 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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Ok I'm listening, but it brings up more questions than answers. I guess first, I was thinking the modules I have (I have 2 of them one works and the other doesn't) were the same as the K250 power section (When I say power section I'm talking Transformer, rectifier, power capacitors and driver board). I didn't know they were different, but I looked after I read your reply pleat and low and behold they're not 5065 drivers they both are 5071 driver boards. Are these that hard to work on or repair? At a glance they don't look any more complicated than the 5065. I need to find a schematic for the 5071 board though and I'll see if I can get the bad module up and running. I don't know much about these, do you know what the wattage is? Do you have a schematic you could email me or someone that has one that I could get a copy emailed to me at cassent5150@hotmail.com Thanks Steve C
Steve C
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| Re: Saving a Frankie [message #14845 is a reply to message #14816] |
Thu, 09 December 2010 12:22 |
stevem
Messages: 4774
Registered: June 2004
Location: NY
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Senior Member |
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I have never seen a K 250 module in person, but they put out the same amount of wattage as the K250s output section does, in fact they may put out more wattage than a fully loaded K250 does!.
As such they should basically be the same in large part.
A different board number could just be due to the driver board being a different size to fit in the compact module, which in turn rerquirs a different board layout.
Really the question I have is if the power transformer the same. They may have chose to use a smaller PT due to the fact that there was no need to have the currrent on hand that the K250s had since you are now minus two preamp boards and the effects board.
My output test have shown that the fully loaded K250 heads output 20 watts less then the non-effects heads due to the higher current draw.
So in short what I am saying here is that in the end, powering your Frank with the module may only give you a 75 to 80 watt amp.
[Updated on: Thu, 09 December 2010 12:23] Report message to a moderator |
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| Re: Saving a Frankie [message #14848 is a reply to message #14846] |
Thu, 09 December 2010 21:58 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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OK, I was mistaken on the driver board it is in fact 009-5021. I have both in hand and they are both Kasino type with the 5021 driver boards and like I said earlier one works and the other doesn't. One powers on and emits a hum to the speaker, I'll fix that one later when I can get a schematic for it. You don't have or know someone with a schematic that I can get a copy emailed to me at cassent5150@hotmail.com do you? They say 100 watts rms on their tag and there is a second tag on the side of the module that has the model(KPN 200-0080-01) and serial (1018). Chicagobill gave me the heads up on a Frankie chassis that was on ebay and I picked it up to complete the restoration of this Frankenstein head and what ever chassis is left I'm going to install the complete module components then decide where to get the 24 volts for the preamps. I'm thinking more towards the resistor, zenear source for the first go at it and see if that doesn't drag the wattage down too much. My biggest concern is just keeping that warm kustom sound rather than all out power. I just ran a test on the rails of the module and its 40 VDC on each side and 78.9 VDC from green to red. Do you have any ideas on the values of the resistors and zenears I would need to install? I would guess 24 volt on the zenears, but what watt? I haven't a clue how to figure the resistance of the resistors. I was told that the K250 did it like this and I could clone that setup but thats 12 volt I beleive and I dont know how to double it to get the 24 volts I need.
Steve C
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| Re: Saving a Frankie [message #14853 is a reply to message #14816] |
Fri, 10 December 2010 14:36 |
stevem
Messages: 4774
Registered: June 2004
Location: NY
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Senior Member |
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Yes that will be another question as there is one black paper cased cap on the reverb board and many other ( most times white plastic cased Mallory) caps on the preamp board and the reverb board that need to get replaced, there failure numbers will be even higher if the amp has not been used for long periods.
In fact if it where me while I was at it I would replace all of the electroliytic caps in the amp.
[Updated on: Fri, 10 December 2010 14:38] Report message to a moderator |
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| Re: Saving a Frankie [message #14860 is a reply to message #14850] |
Sat, 11 December 2010 14:23 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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Yea, they say 100 watts on the side tag of the module. I might be dragging it down a bit by powering the preamps from the same transformer. I dont exactly have it figured out yet. I'm kind of waiting on the frankie chassis I just bought the other day on ebay to get here and see if I can restore this head back to original. Then I'll see about putting the module in the spare chassis. At this point its unknown if the preamps even work. I wont know that till I get the missing parts in to find out. That is a good idea to replace all the electrolitic caps like stevem said. I'm going to see what I got to work with first and go from there. Thanks Steve C
Steve C
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| Re: Saving a Frankie [message #14878 is a reply to message #14870] |
Mon, 13 December 2010 22:58 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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I will have to come back to this. This is great info stevem. Ive got so much going right now, but this is what I was thinking of doing. Just so I understand, your taking positive from the red positive wire leg of the power cap via a power resistor to get the voltage dropped to 24 volts. This will be the source for the postive terminal of the 7824 type regulator. The chassis is the ground for the preamp CORRECT? The postive output from regulator is the red wire postive input to preamp. I think the reverb board gets power from the preamp doesn't it? This chassis come to think of it, wont have effects. I bought a complete chassis off Ebay and it hasn't got here yet. I'm going put that 100 watt module components into which ever chassis is left. Steve C
PS I'm kind of elbow deep in a little Challenger at the moment. Having issues with a tremolo like effect to the output. I cant seem to get rid of it ,cant turn it down with the controls and cant shut it off with the brown wire. I did notice that there is a .1 DC reading at the out put of the intensity control when tremolo is on and when you switch it off it drops to O. I dont know if its on this thread tho.
Steve C
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| Re: Saving a Frankie [message #14952 is a reply to message #14884] |
Sun, 26 December 2010 20:29 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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OK I finally got the Frank chassis and am having a look. This is a model C-495. The chassis is powering up. left channel no or faint signal getting to speaker. right channel has a very weak signal. I've got DC readings on the power caps and the right side of the transformer mounted on the inside of the back plate on the left side. It still has the cardboard caps in the preamp along with the white plastic ones. Looks like this is the one I'll restore first. I dont have the radial caps for this so I'll get by the parts store and see if I can find replacements for all the caps and transistors. Germanium transistors that will be sweet!! I haven't tested any components yet. I'm going to get all the new parts I can and update this a little first then test whats left. Does anyone have a schematic for this C-495 they can Email me at cassent5150@hotmail.com ? Thanks Steve C
Steve C
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| Re: Saving a Frankie [message #14984 is a reply to message #14826] |
Fri, 31 December 2010 17:36 |
cassent5150
Messages: 341
Registered: August 2009
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Senior Member |
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OK I have some update info for YA"LL: I got the 24 volts I needed from the power cap + red wire terminal of the module through a 24 volt zenear diode, reading 28.3 volts out and sent it to the + red wire on the frank chassis. I grounded the module chassis to the frank. I pulled the power from the same cap terminal for the power light on the frank and voala!!! Powers on and both channels work fine. I did notice a lot of signal so for good measure I dampened the signal through a 100K resistor to the input of the module. Things went a little distorted so I went with 2K and so far all looks good. The reverb gets real deep and theres plenty of clean volume. I replaced the 500uf paper cap with a 416 uf 100 volt on the reverb board, it was a good fit but do you thing thats going to be a problem? I now have to decide what I really want for this output section. The modules are 100 watt rated not to mention rare and I have several of the K-III models I never use and not very collectable I might add, rated at 125 watts. Hummmm what do you all think? Steve C
Steve C
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