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"help with a Freedom amp please "

Started by dg, December 03, 2009, 02:04:51 PM

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J M Fahey

Hi DG.
I'll check the switch and answer, but there's something I don't understand by the way you phrase it.
1) Is the amp working now, meaning you plug it straight on 240V, you turn it on and play?
*or*
2) you *guess* it works, because "it used to"
*or*
3) you use it with an external transformer?
I ask all of this because any factory powered original amp, made in California, would have come with a 120V transformer, and besides that, that male power socket mounted on the amp's wall is a typical twin parallel flat blade 120V connector.
Of course, it *might* have been made in 240V for a British client *or* said client could have replaced the transformer for UK use, still keeping the original USA connector.
Please answer that before we can continue with this.
Speaking of Great Britain climate, my family comes from County Cork, Ireland, where it's shorter to state that it does *not* rain for 5 days a year.
That's not that bad, considering all that warm seawater thar runs by the "Emerald Island" provides a very humid climate but quite softer winters.

dg

Hi Juan its option 1
Quoteplug it straight on 240V, you turn it on and play
yes I just Plug it in works great, takes a while to power down ,
surely it wouldn't work if it had the US 120v transformer in it ?

My folks are originally from Garrynagree "we do get about us Irish LOL" My mother has never fully settled here 40 years on ,she still occasional mentions the "hard water, no decent bread ,different sunlight, the cold ,the heat, the cats appear to be different here as well LOL and how washing always dried quicker at home ,she cant explain the physics of it, but I will keep asking LOL

Have a good day
thanks
david     

Brymus

Its nice to see someone using one of these amps ,and you are in good hands with JM guiding you.
I stumbled across the original Marketing for one of these amps when I was looking for something else, and they had ads with topless woman they were going to run but didnt in the USA.
Ah yes it was some research on an EH pedal that led me to it.
Anyway the "Freedom Amp" was part of my motivation for getting into SS DIY.
When you are done could you post some more pics?
Maybe some sound clips too?
I love going back in time with this kind of vintage SS gear.
Good Luck,it sounds like you almost have it sorted.

dg

Hi Brymus ,Juan really seem to know his stuff and I'm very keen to get the amp safe and working as it should, and he is being most helpful and informative
I'm keeping a little log that I will post with pictures on the forum when its finished and will update as I work on it
I am absolutely staggered at the sound quality, my friend played through it and is now looking for one (This man with a collection of  vintage valve amps!!!!!!) he said it was the most percussively responsive transistor amp he had ever played (he's also a staggeringly good guitarist)

I have had a looked inside and can't find any topless woman LOL
Thanks
david

J M Fahey

Hi DG. I've been checking the Maplin catalog.
Order
1: "Fused Snap-In IEC Chassis Plug with Switch" Order Code: N94CZ
1:"Bridge Rectifier" KBPC606
1: Pack of 10 fuses, they call them " 20mm Glass Quickblow (F)" and the full code is:20mm QB 1A 10 PK GJ90X
1: mains cable that suits you, with a female IEC connector and a 3 pin grounded male mains connector.
When you get it , put the switch and bridge on a sheet of white paper (to get a clean background) and take a couple pictures, legs-up and legs-down.
Also a couple real close up pictures showing from different angles the original round bridge and its connection to the filter capacitor.
You'll replace it with the new bigger one trying to keep everything as "original" as possible, to make errors difficult to happen.
I trust you can solder well, have a good 40 to 60W soldering iron, good tin, long nose pliers and a sharp wire cutter, plus some good PVC electrical tape.
Good light and glasses, if necessary, help a lot.

J M Fahey

Hi DG.
Just to know what your amplifier would look like if you turned it into the battery powered version:
http://electroharmonix.ronsound.com/index.php?option=com_content&task=view&id=62&Itemid=45
No, it's not a Panasonic Battery ad, although it might.
No wonder they converted them into AC powered units !!
The amp design itself is lovely.
I will build its preamp (to be used with one of my regular power amps and speaker), to see if it has as much "bite" as they say.
I guess I'll like it.

awdman

Talking about 40 D-Cell batterys that's about $80.00 dollars not so free.

dg

 Hi Juan I have got the parts ,HeHe and I found a piece of hard 3mm black plastic I could use to mount the switch or I have some aluminum tread plate?

Are the positions in relation the the + the same on all Bridge Rectifiers?


+   s2
s1   -


if so

(1)The + is connected to the three center prongs then out via the white with a stripe to the circuit board

(2)to the left of the + (s1) is orange (and goes to the transformer?)

(3)to the right (s2) green goes to the top panel switch

(4) The - goes to the outer prong on the aluminum tubes case then via a yellow wire to the circuit board

(5) picture of the back of the switch
thanks
garry

dg

Hi Juan thought I would add a picture of the large silver thing that the bridge rectifier it attached , also there are two identical black wires going to the old two prong plug socket you can plug

the mains lead  can be connected  in either direction (up or down)
how would I know which one goes to the live and which to the neutral ? my friend told me that the correct way to put the mains plug in and to connect a guitar lead to just the amp and hang the other ends jack plug in front of the amps speaker and  then disconnect the mains plug reverse it and the position with the least hum coming from the amp was right?

he said he did this many years ago with his two prong amp lead ,but was not sure if its correct and he has less knowledge of electronics than me (if that's possible LOL)
many thanks
david 

PS the silver thing and the transformer? Are mounted on the bottom of the amp with bolts that can be touched from the outside should I re mount them on a block of ply inside?
Many thanks
And thanks for the link I see what you mean about using  lots batteries LOL




dg

Hi Juan (starting to get the hang of this posting LOL)
sorry should have read

(1) there are two identical black wires going to the old two prong mains plug socket but it can be  connected  with the amp mains lead in either direction (up or down)
how would I know which one goes to the live and which to the neutral  on the new switch?

(2)you metioned grounding (pic two) is the new switches earth going to the twisted arrowed bolt?


(3) bolt at the bottom of the amp should i put it all  inside?


many thanks
david

dg

Hi juan I have mounted the switch /mains socket on a hard plasitc plate ,routed a larger hole (to cover the old one) but conected the Original mains one back as it was and its inside the amp (see pic) When I know the correct way to wire the new mains switch should I use crimped connectors or solder them?
many thanks
david

I am very excited and really looking forward to using the amp safely
 

J M Fahey

Hi DG.
You have shown a good intuitive grasp of what had to be done.
Since (as they say), an image is worth 1000 words, here go 7000 words equivalent.
The main thing here is that the new green/yellow wire must be firmly soldered to the earth pin on the switch back, to a solder lug clamped at one of the transformer bolts, to ground its frame, and to one of the front panel bolts, to ground the rest of the amp.
After you have done that, be creative with a piece of string and tie those long hanging wires forming some "pack" to avoid wire cutting because of unnecessary flexing during transport.
You must also use some hot glue to attach that floating rectifier to the silver  filter capacitor for the same reason.
The new bridge goes exactly the same as the older one, pin for pin.
Post some pictures of your work of art, and, more important, some MP3 to hear it.
Feel free to clear any doubt.
JMFahey

dg

Hi Juan many thanks for the pic and help just a  couple of questions
QuoteYou must also use some hot glue to attach that floating rectifier to the silver  filter capacitor for the same reason
PICTURE (1)filter capacitor has a bolt on bracket i just removed it for the pictures

PICTURE(2) there are two identical black wires going to the old two prong mains plug socket from the Transformer but it can be  connected  to the amp mains lead in either way(up or down) this is the bit i,m worried about!!!!
how would I know which one goes to the live and which to the neutral  on the new switch? is my friends suggestion correct?
many thanks Juan i will add an mp3 and more pictures when shes up and running
david




J M Fahey

Hi DG
Very short answer, I'm going to sleep.
1) The capacitor has a bracket, what I want you to fix it somehow to the bridge which is floating in the air, with two red wires pulling it.
Hot glue those red wire solder points to bridge body and reinforce bridge pins to capacitor.
Even snap a small piece of wood between bridge and capacitor and glue it to both.
What you don't want is any "play" there which might crack some pin.
2) One black wire to Live, one black to neutral, they're floating so it's the same. Grounding is now achieved through the Earth pin.
Solder everything.
As an extra safety check, a neon screwdriver to the chassis must not light at all, never, with amp on or off.
Post the pictures of your work.

dg

Hi Juan I couldn't get any specific earth wire so an electrician at the shop said to strip the 3 core from standard mains cable and use that(is that ok?) I bought a neon screwdriver and have tested the top panel ,I bought a new soldering iron and soldered everything I will make some wood blocks to hold the wire and bridge steady .it all seems to working great I have enclosed a couple of pictures the solderings getting better , no dry joints just a little to much solder  tell me what you think
Many thanks for your help
Garry