All things LA2a related

[Scenaria]

[quote author="CJ"]

Steve, they wanted 75 bucks to send you that case of beer priority, so I opted for the 7 to 10 day thing. I hope your not pissed. But you will have to take a big piss in 7 to 10. :grin: :guinness:[/quote]

how could I be pissed... hell beer is on its way! coulda used it today though...

damn fridge died... completely defrosted... lost all my food

 

[CJ]

Hopefully the Beer will get there before hurricane season starts.
Predictions indicate 5 landings this year. Sheesh. How do you guys stand it?
:shock:

 

[Tom]

Hello everyone:

I am relatively new to DIY recording gear, and this is my first tube project. I have started on my Bloo kit, and have a few questions.

Can someone explain to me the function of R38 (22k) in the Bloo kit?
I cannot find this resistor on the LA2A schematic, which is provided at the end of the Bloo instructions.

I note that CJ? posted an image that listed differences in LA2A versions and two of the versions did not include an R38, the latest version used 220k (compared to 22k).

I am trying to understand the function and purpose of each component as I assemble the kit. Yea, its slowing me down, but its a lot of fun.

Best regards

Tom

 

[Scenaria]

R38 is not needed if you are using the older schematic.

heres the deal

either pick one or the other...

R29 4.7k 2w
R34 10k 2w
R38 22k
C13 510pf

OR

R29 4.7k 2w
R34 22k 2w
NO R38 or C13 is really needed

two revisions of the schematics... one isnt really any better than the other..the onewithout R38 is an older revision.. the one with R38 is a newer revision... pick one and stick with it

 

[Tom]

Scenaria:

Thanks for that info. After reading your comments, I managed to track down a link to the newer schematic in another thread. With new schematic in hand, I will plod on.

Best regards

Tom

 

[Jim50hertz]

Hey scenaria

I have what will seem to many as a real dumb question...

I'm currently in the final stages of hookup with my Bloo 2 and am a little confused with the (UK 240V) power transformer wire configuration...

in the bloo manual the blue wire is listed as 240V neutral and the white wire as LIVE. and in the Link box it says Brown-black.


Does this mean that I link Brown and black to give 240V? or, does it mean I hook up both BLUE and BLACK to the neutral terminal on the power connector, and the BROWN and WHITE wire to turret B25 (BLOO manual page 21) and from there to the live terminal of the power connector?

I'm gonna leave those connections for the moment and hookup the front panel

Jim

 

[Scenaria]

if you look on the transformer box you will see the taps.. diagramed

theres two primary windings that need to be linked together for 240V opperation

tie the brn and blk leads together

use the white as your neutral and the blue as your hot lead..
you should be fine


or the other way around.. it really doesnt matter which one you tie the neutral too.. its AC anyhow

 

[Jim50hertz]

Thanks Scenaria :grin:

that's what i thought but just wanted to be absolutely sure

cheers

Jim

 

[CJ]

Dang, bootleggin the UK also?
That's it. I'm callin UA. :wink:

 

[Jim50hertz]

Och Aye

Even as far north as bonnie Scotland! :wink:


Steve, is C6 (.01uf) used? Can't find any trace of it in the Bloo build manual.

Jim

 

[Scenaria]

its listed on page 5


yes... you use it

 

[Jim50hertz]

Yup, I see it, I've looked through the manual several times to see where it is positioned but can't find it, am i missing something really obvious? I've got cayacosta's graphical representation which suggests it goes somewhere near the variable cap but I can't figure exactly where, can ya help?

Cheers

Jim

 

[Scenaria]

that variable..cap your looking at is not the one on the turret... its the one thats used for stereo linking..

same with C6

unless you intend on running two in stereo you can omit C6 and C14

I put it in the list for anyone who wanted to get all of the parts.. but not may seem to be inclined to run la2a's in stereo

 

[Jim50hertz]

Aah! I see....

Thanks again steve

Jim

 

[Jim50hertz]

Ok I'm gonna ask one more foolish, naive question today and her 'tis...

R23, the 6K8 resistor which goes on the three pole switch is the only 0.5w resistor I'm missing, however, I do have a !/4 watt metal film 6k8 which i could use in this position...

Will i get away with this or should I just be patient and order a 1/2 watt?

(I REALLY need to learn more about circuits and I must thank ya for your patience with all these questions)

 

[CJ]

Steve, you got an 1-800 number? I'm having problems with Windows 2000. :grin:

 

[Scenaria]

you should wait for the 1/2 watt OR go with a couple 1/4 watt in series.. maybe a 5.7k and a 1k in series or something?

oh and yea call..

1-800-chris-jenrick

:green:

 

[Jim50hertz]

nice one steve :grin: :grin: :grin:

gonna order the carbon comp 1/2w 6.8k and use a metal film 5.62k and a 1.24k 1/4 Watt in series for the moment so i can fire up and test tonight.

thanks again

jim

 

[dukasound]

Hi
Does anyone measured both voltags on power transfomer?
Please I need off-load voltages.
Thanks in advance
Duka

 

[Jim50hertz]

ok, so i finished the wiring tonight and fired her up,

without the tubes in i measured 6.3 AC between A24 and A25 , DC at B21 was 369 and at B20 366 and A1 59V...

I figured they read ok and in the ballpark so i put the tubes in and did some more measuring...

B21 Read 347V
B20 - 268V
A1 - 59V
A20 - 73V (Should be 131!)
A14 - 221 (Should be 216)
A19 - 93

I reckon most of these are ok apart from A20 which is way off!
Oh yeah and the neon gave out about half way through takin these readings

i'll double check the component values in that area and look over the whole circiut in the next couple of days.

thanks for the help today steve, should be happily squishing vocals by the weekend if i can work this out.

cheers

Jim