Jukebox Amp question

[loman4ec]

As I posted a few weeks ago I just bought a Rockola 1454 juke and it is at my step dad's in his garage. It does not work and I am sure it needs a rebuilt amp. My question is for the time being is it possible to buy an amp out of another working box and install it into this juke? Also I have heard in a few posts mentioning about some boxes being converted to solid state with new amps. How hard is this to do and can it easily be changed back. My reasoning behind this is my step dad says he would use it in his garage if it worked for the time being. ai will only be home for a few weeks next month and I don't have time to go through and rebuild the amp while I am home. So I want to do something just to get it running. I will keep everything and put it back to original when I restore it in a few years. I just figure he is nice enough to let me use his garage for storage and if he wants to play the juke when he is out washing his car or working on his Fat Boy I would like for it to be possible. Any suggestions???

[loman4ec]

On a different note how hard are these amps to rebuild? We have always sent them out to be done. I can buy the tube kit and rebuild kit online for only $130. Thats not bad. I am not a pro when it comes to electronics but I do have experience. What do you think. Can it be done by a novice or should it be sent out to be rebuilt?

[BrianB]

Josh,

To be perfectly honest with you, rebuilding an amp isn't super hard. It really helps to have and electronics background though. Replacing caps is pretty straight forward, But..... There are always curve balls. My Seeburg "B" amp was originally configured one way out of the factory and then later on it's its life Seeburg basically made an engineering change to them which required them to be changed in the feild by authorized technicians. My amp only recieved half of that change.

You will need a good schematic, the ability to read it line for line, know what the various tolerances are for you caps and your resistors and have good tubes. By ordering the entire kit (tubes & caps) you save yourself the hassle of ordering the right items individually by yourself. If anything, even if all of your existing tubes are good (assuming it came with any) you now have a full spare set which is great to have.

I personally buy my own caps & resistors seperately. I've found it to be cheaper that way. I also test my tubes when possible on my tube tester. I also replace any damaged or brittle wiring, clean or replace any dirty or damaged volume potentiometers or selection switches and give the amp a good cleaning.

The tools that you will need for a basic capacitor/resistor remove and replace are:

! - Good soldering skills/technique and a decent soldering station
2 - Flux
3 - Solder sucker or solder wicking
4 - 40/60 Solder (40% Lead / 60% Tin) The newer stff, lead free, is no good for repairing old amps or any vintage electronics.
5 - Multimeter
6 - Small Screwdrivers
7 - Wire strippers
8 - Wire cutters

Also, unless you have the ability to bench test the amp properly wither by simulating all inputs and outputs. It's good to have a jukebox around to hook it up to for testing & troubleshooting.

You can put a solid state amp in it and never have any problems for a very long time. I have heard from a lot of people, and agree, that tube-type amps provide the best sound. You talk to any guitarist and they will tell you that a tube-type guitar amp offers a much more "warm, real & rich" sound. I personally wouldn't switch the original amp out for a solid sate one.

If you are in a super fast hurry to get it working I would send the amp out.

What is the general condition of the amplifier right now?
 

[Kilroy]

I second Brian's thoughts. If you can read a schematic,  have soldering skills and an understanding of basic electronics the hardest part is the time involved.   

Bill Bickers (Jukebox Friday Night)  offer free support with his cap kits,and a schematic,  you may not need to call him, but  it gives a  sense of comfort. 

You can prolly find an amp, on Ebay, from Durfee or  the Jukebox Junkyard, but most parts places  don't recap, so you're in the same situation you are now. As a short term bandaid, I'd think of putting in a solid state amp so  it could be used until you get back stateside for  good

[BrianB]

Bill Bickers is probably the worlds best authority on jukebox amps. I really do mean the WORLD. He's been in the business for decades. Quite a nice guy as well.

[Skeleton Man]

I'm only a novice in the world of jukeboxes but I'll chime in my with 2c (or a nickel lol).

I'm in the process of rebuilding the amp from my Wurtlizer 2600, and having a schematic is handy. I just bought a reprint off ebay for $25.

I replaced the tubes in pairs from ebay coz in my case it's $260 for the tube kit alone (8 or 10 tubes total, I forget which), but $130 for the tubes, caps and the works sounds like a good deal to me. I did buy a capacitor kit to save myself the trouble of finding them invdividually and that has worked out well.

The kit I bought has sticky labels on each part with the number from the original schematic (e.g.  C22 or R27), and even comes with a photocopy of the amp schematic. I got mine from Jukebox Friday Nights but I don't know enough to reccomend them over anybody else.

For hard to locate parts I'd highly reccomend John Durfee at Durfee Coin Op - I'm in Canada and shipping has been fast and very reasonable! within the USA is probably even better. I'm about to place another order any day.

Ebay is a good tool too - I won a 261B stepper for $10 (the guy I bought the juke from wanted $150!)

Soldering is easy - you don't need a great deal of experience, these things were hand soldered so there's room to move. I dunno about the tin/lead vs unleaded solder, but one thing I noticed is the old existing solder takes an extra few seconds to melt versus the fresh stuff.

Now as for testing on the bench, I am still trying to work out the best approach here and if i need to hook anything up to the chassis connector to make it work. I don't know if these amps are always on and just muted til selection, or only fire up when a selection is made.

I'll be following this thread myself 

[Jim]

I just bought a reprint off ebay for $25

Chris, does this mean you don't need the PDF for your 543 Amp...?

[Skeleton Man]

Chris, does this mean you don't need the PDF for your 543 Amp...?

I still want the PDF coz it's a digital copy I can zoom, etc. The paper book is so I have complete literature for the whole machine.

Chris

[Ken Layton]

Quite frequently these old amplifiers will also have some of the resistors go off value and need to be replaced. Changing capacitors does not neccessarily fix these amplifiers.

[loman4ec]

Ok I feel that I have the knowledge and the tools to do it myself. I will order everything prior to coming home so they will be there when I arrive. Thank you all for your help.

I do have another question. SInce this box is not for resale but for my personal use wouldn't a solid state amp be much more reliable? I understand that the sound is not quite as good but I can't imagine the difference being that great. If I kept the original amp it wouldn't hurt the value. Does a lot of modification have to be done to use a solid state amp? Where would you buy one and what kind of amplifier would you need? I just want to compare the cost of both. I already have a ton of work to do in the three short weeks I am home. If I had a plug and play option I would take it of the price was right. Even if it is only for the time being so mu step dad can enjoy the box while I am gone. After all if he wants to use it I figure I am getting free storage. That is the least I can do. He is not handy at all. He would not be able to do any work on it in any way whatsoever.