[fordgtlover]

You might consider wiring the amp up, but not plugging it in to AC, and then posting some detailed pictures showing how you have connected everything. People here can review your work before you power it up.

As a few tips to try and keep you safe:
- Don't leave exposed 240V AC in your amp. (use covered crimp connectors or heat shrink the ac connections to the IEC connector and avoid exposed wires out of screw terminals).
- Make sure you securely bolt a ground wire to exposed metal.
- Make sure you are clear which pin is the Neutral and which one is the Active pin on the IEC connector.
- Make sure you use a fuse on the Active line.
- Check that all of your connections are correct, and check again, and then take a break and then check it all again.
- When you finally do power the amp, plug the IEC socket in, then the wall socket and then switch on the power from the wall.
- Don't stand too close to the amp when you turn it on.
- If your [correct size] fuse blows on startup, turn the power off at the wall and then pull the plug out. Check and recheck everything and find and fix the problem before you power it up again.
- When checking voltages etc on a live amp, don't grab the amp or anything inside the amp with both hands (keep one hand behind your back if you have to).
- Have someone nearby when you first power the amp, and explain to them how to turn of the power (wall switch) if needed.

The key thing is to work slowly and carefully, and understand what you are doing and why and that you are connecting the right things to the right places. And, ask question if you need to, silly questions are easier to deal with than silly mistakes.

 

[nsx_23]

Quote:

Originally Posted by nickyboyo /img/forum/go_quote.gif I'm off out for a few spiritual beers, being Easter long weekend and all i will post all the parts i used on my power section in the morning, then i can just send you pictures of what goes where- it's a piece of cake bud. By the time you have the amp kit, psu and toroidal transformer you will be more than ready for wiring the thing into the mains.

Cheers mate. Its just that I'd rather do my parts shopping in the one hit since Jaycar isn't exactly close by...

I'd probably go buy the parts on Monday. What power cable do I need as well (I'm assuming the transformer and socket doesn't come with one)?

Alternatively, would it be possible to shove one of these in a Zero?

Fordgtlover, so how do I hook up the ground wire? I'm getting slightly worried again.....

 

[fordgtlover]

Quote:

Originally Posted by nsx_23 /img/forum/go_quote.gif Cheers mate. Its just that I'd rather do my parts shopping in the one hit since Jaycar isn't exactly close by... I'd probably go buy the parts on Monday. What power cable do I need as well (I'm assuming the transformer and socket doesn't come with one)? Alternatively, would it be possible to shove one of these in a Zero? Fordgtlover, so how do I hook up the ground wire? I'm getting slightly worried again.....

The transformer will not come with a socket or power cable. Typically you would use an IEC socket. Such as one of these.
IEC Male Chassis Power Plug with Fuseholder - Jaycar Electronics
IEC320 Male Chassis Power Plug - Jaycar Electronics

And the power cable is the same type that you use to plug in your computer - an IEC power cable.
IEC 240V Power Lead - 2mt - Jaycar Electronics


In the first post of this thread, johnwmclean's first picture shows a green/yellow wire from the black IEC socket at the back of the case to a bolt attached to the bottom of the chassis. This is an earth (or ground) wire.

 

[TOM 1]

sorry to rehash an old thread, but I thought my question was relevant. I have built a Jaycar amp, i've had it for a few years, and it's completely stock. I'm looking at doing some mods, but I'm know nothing about electronics really......I'm still amazed after all these years that I managed to get sound out of my amp. On reading some advice, I'd like to get a couple of OPA627 op amps onto the board somehow. Does anyone know if this can be done, and if any other mods need to be made in order for it to match? The original opamp in the kit is soldered to the board, and I've only seen the 627's on something called a 'browndog'. The browndog has the two single opamps mounted, and has 8 pins a the bottom. The original opamp has eight pins, but they are alot closer together than the browndog. How would one go about attaching this to the board?

 

[johnwmclean]

Cut the legs off first but leave as much leg attached as possible so you have something to grip, apply a small amount of solder to the end of you iron and heat the pad on the underside of the pcb of one of the legs, on the top side of the pcb with pliers pull the remainder of the leg out once the solder has melted, repeat for each leg.
Now you’ll probably have remaining solder in each of the pads, use copper solderwick to get the majority of solder out. You may need a small solder pump to get the rest out, as the opamp pads are quite small, solder gets tricker to remove.
I use this method: with a small rubber pump (Jaycar has these), add a very small amount of solder to the end of your iron, heat the solder from the under side of the pcb, and pump out from the top.
So you’ll never have to do this again you need something like this:
8 Pin Gold Insert Machined Pin IC Socket - Jaycar Electronics
Once you have the socket in place, you can pull out and put back any opamp you wish to try in seconds.

 

[TOM 1]

John, thank you so much for you help. I'll order one of those tonight. I have seen those things in pictures of member's amps and wondered why mine didn't have it. So then how do I connect on of THESE to that IC socket? It appears as though the pins on the bootom of the browdog are wider than the holes in the socket.

 

[johnwmclean]

Tom,



You’ll obviously have to solder the socket into position first, the pins on that opamp you’ve referenced should just push into the 8 pin socket as this picture demonstrates.

 

[Wilf]

If anyone is interested, there is a group buy being organised for the JLH ripple reducer PCB, that really makes this amp sing. It's central the the SandyK mods, especially if using the LM4562. Any monies raised goto Cancer Research.

index

Will (from the RG)

 

[elliot42]

Just curious, John, what are those 'hats' on top of the Nichi FGs?

 

[johnwmclean]

Quote:

Originally Posted by elliot42 /img/forum/go_quote.gif Just curious, John, what are those 'hats' on top of the Nichi FGs?

It’s not my build Owen, I was wondering the very same thing, they look like crystals

 

[amb]

Looks like the stick-on rubber feet that come with Hammond 1455 cases... someone thought that the caps needed vibration damping?

 

[johnwmclean]

Quote:

Originally Posted by amb /img/forum/go_quote.gif Looks like the stick-on rubber feet that come with Hammond 1455 cases... someone thought that the caps needed vibration damping?

That and resistors there sitting on

 

[elliot42]

Quote:

Originally Posted by johnwmclean /img/forum/go_quote.gif That and resistors there sitting on

Right... they do look peculiar. I still can't imaging what they could be for.
And I must agree about the odd placement of the caps on top of the resister. The resistors all look like they could be a little more flush to the board as well.

 

[SP Wild]

Finished the Jaycar amp last night - fully operational.  Hooked everything up yesterday and two LEDS weren't working...the PSU regulator for the -15V rails were heating very hot, the LEDS that did not work were on the -15V side.
 
Went out, bought a 15 buck multimeter from Super Cheap Autos and checked that the amp board is not shorted to ground from any of the 15V rails - OK...check out put of PSU - receiving only -8 volts when it should be-15v???  It was 4:15pm and Jaycar shuts at 5:00pm...I have half an hour to find the dodgy component if I wanted to listen to this thing at night.  This is just like work...diagnosis with speed to beat the order cutoff time for spare parts.  Its like a duck taking to water.
 
Luckily the +15 volt was functioning correctly, this made my job easy...checked voltage drop against all components from one side to another and voila...located an incomplete track - or open loop from ground...wired a solid core CAT6 strand on the underside and try again.
 
All OK!!!  Not bad for a first attempt at soldering anything other than joining 2 wires in cars.  Diagnosis was much easier than I thought - you guys should try diagnosing electronics on a modern German luxury car...if you don't have to strip the interior, dash, seats carpets and all - its not really diagnosis!!!
 

 
 
Sounds good, laid back, mid centric - I like it, although the Lehmann BCL is certainly more refined, stock, I'd say this amp is in the Xcan V3 league in terms of refinement.  I won't mod or box this, I didn't realise it was going to be less challenging than I imagined... now I have full confidence to find out for myself what the fuss with the B22 is all about.
 

 

[SP Wild]

I want to purchase another Jaycar kit to bridge them together for balanced operation - is it as simple as it appears on tutorials for bridged amplifiers?  I have a and Audio GD Reference 7 dac coming in perhaps this week but do not own a balance headphone amp - the Rrf 7 only uses half its circuitry for single ended use - I would have no means of "burning in" the two unused channels.  I can pick up another kit very cheaply and created a balanced headphone amp, if this is feasible.  Thanks in advance.