WA KT88VA XL Build

[konig]

I am starting this build in parrallel with the Wilmslow Classique speakers. I know that this amp build has been covered by several others so this post is more of an interest check to see if there is demand for another thread on this ??

so far spent 2 hours checking and identifying components (gulp

) and printing off the build instructions....

 

[jonjin]

Always... especially the speaker build

JJ

 

[DB]

Hi Konig,

I certainly want to see your build!

I remember the component checking session well, I sat on the floor for 2 hours checking and double checking, could barely bloody move by the time I'd finished, unhealthy old git that I am!

Cheers

Dave

 

[konig]

ok donea few bits & pieces, fitted the sockets etc and re-read the instructions a couple of times.

Question - how do you test your mains voltage be it 220v or 240v does this matter in the context of it being used in the UK??

 

[i_should_coco]

Mains voltage in the UK is 240V. Despite the fact that it's nominally specified as 230V to fit in with Europe.

They specify it as 230V +10% -6% which allows them to keep it at 240V while on paper complying with Euro-regs.

 

[konig]

thanks that's one less thing to worry about then

 

[konig]

Hi all, next question..

Does everyone use rubber gloves when testing as suggested in the instructions..?

I thought I saw some on the web on one of the sites that sells kits but can't find it now....

just started onpopulatingthe TAG boards, pic to follow..

 

[konig]

first tag board complete. was unsure about the 100R resistors as the ones supplied didn't match the photos of the completed boardin the instructions. checking the colour codes confirmed they are the correct value though .... any experts please shout if I am wrong. shown below 6th tag in from left and right

 

[konig]

whilst I am completing the other tag boards I have been reading ahead in the instructions. I think I am going to have to make a call to WA as one paragraph is not clear

'tightly twist the black wires from the secondary of the power transformer to the tags for the47R resistors'

does this meanone black wire to each of the two resistors? Can't make out from the photos..

'Tightly twist the red wires from the secondary and connect to the AC tags of the bridge'

no reference to AC tags....or the bridge - again not clear in the photo supplied - dont know what these refer to.

any clues ...??

 

[DB]

Hi Konig,

I hope I can shed some light on your confusion regarding the PS tagstrip - The black wires do indeed connect one to each of the 47R resistors - a look at the power supply circuit diagram should help to clarify.

Similarly the red wires go to the AC side of the "Bridge" rectifier formed by D5, D6, D7 and D8 - when looking down into the underside of the amp it's the lefy hand side of the tag-strip where the red wires need to connect. I suspect that the reference to bridge is a left over from the non-XL version of the kit which I believe uses a one piece bridge rectifier.

Have fun

Dave

 

[konig]

thanks Dave thats what I assumed but good that you clarified.

just populating the input boards and noticed that WA have supplied 39k 3W resistors instead of the 33k - quick call to WA and they are sending replacements ..

 

[konig]

Completed the first input tag board last night - if I cansolder a tagboard per night this week then hopefully I will be ready to test power at the weekend !

 

[Dik Dolan]

Nice one=)

Savour every moment of the build...and take lots of pics so we can letch at all the lovely naked resistors and caps and wires and valves... sorry got a bit carried away there.

©¿©¬

 

[konig]

Dik Dolan wrote:

Nice one=)Savour every moment of the build...and take lots of pics so we can letch at all the lovely naked resistors and caps and wires and valves... sorry got a bit carried away there.

©¿©¬

oh go on then...

leftdriver board ready to fit - quite a few links on this board so takes a little time

all components identified for the right driver board and ready for the next solder-thon. must admit I am a bit tired tonight so wont start this until tommorrow.

 

[konig]

completed the final tag boards and now forsome wiring up and testing the power supply. Managed to get some croc clip probes for my multimeter for that job.

 

[konig]

funny when you look at the pics it really shows my amateur soldering skills

- , anyway I have been testing for continuity as I go and have did spot a a couple of dry joints that way.

 

[Ant]

soldering looks fine to me. Good job.

 

[Matt J]

Those helping hand thingy's are a god send

 

[konig]

whilst I am *still* waiting for the driver to finish my Classique speakers, thought I progress the amp a little more.

wiring it up seem much more satisfying than populating the tag boards. Feels liek you are actually building something. some of the power supply wiring ..

from the back - remember this is the hair shirt (non-integrated version). there are blanking plugs for remaining input holes to fit at the end.