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Kerry Design mini GRHV\GRLV and JoaMat mini T2 Group Buy

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i would like to get in the group buy.

for me please:

  • 4x GRHVxxx 
  • 2x GRLV79xx
  • 2x GRLV78xx
  • 2x Main Board
  • 2x miniT2 

- bare boards.

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  • I am moving Kerry's mini GRHV\GRLV GB discussion to its dedicated thread here. I also included JoaMat's mini T2 here to see if we have enough interest for a GB. The table will be updated periodic

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@mwl168, can you adjust my order to move from 4 pre-assembled GVHVxxx to 2 pre-assembed and 2 bare?

on your spreadsheet:  2, 2, 2, 2, 2, 1

Thanks

Please add the following to my order:

1x PSU main board

1x GRLV78

1x GRLV79

2x GRHVxxx (bare PCB)

Could I be added with the following:

4x GRHVxxx - partially populated
2x GRLV79xx
2x GRLV78xx
2x Main Board
1x miniT2

Cheers,

  • Author

Table updated. Please do double check and let me know if I have made mistakes.

 

I will tally up the final board counts and get quotes from the fab house. I will then update the table with board costs and the total due for each participant and start collecting payments.  I will place the order when all payments are collected.

Please note the payment will include boards cost and shipping charge from the fab house to me (shipping evenly distributed to each board) but will not include shipping charge from me to you.

 

The following participants are dropped from this GB due to no response:

Marc Edwards

stickyjon23

zumac99

 

Edited by mwl168

2 hours ago, mwl168 said:

Table updated. Please do double check and let me know if I have made mistakes....

This:

         "Dear Michael, increase my GRLV78 XX, GRLV79xx numbers to 3 each from 2, please! Thanks!!"

 

 

Dear Michael,

Please add one more main board for me. So, the new total is 4 main boards.  The rest are correct.

Many thanks.

Wachara C.

Could you increase my GRHVxxx bare PCB from 6 to 10? Otherwise I'm good.

Thanks!

Michael,

Add 2 mini T2 boards.

Thank you,
Joachim

How many of these boards are needed for a mini t2 build? I would like to get it for 1 mini t2 and potentially a psu for 1 kgsshv carbon

Bare with me as im pretty new to the ES amp building.

Michael,

Could you revise my order to just 5x mini-T2 and no psu? My friend backed out so I think 5 is enough for me.

Thanks again!

  • Author
14 hours ago, boinger said:

How many of these boards are needed for a mini t2 build? I would like to get it for 1 mini t2 and potentially a psu for 1 kgsshv carbon

Bare with me as im pretty new to the ES amp building.

For a complete PSU, you need 2 GRHVxxx, 1 each GRLV78xx, GRLV79xx and the PSU main board. GRLV78/79 can be replaced with 7815\7915 regulators.

Each mini T2 set includes a left channel and right channel board for a complete amp.

With due respect, with high, lethal voltage, SMD, etc., this is not a good project for a beginner to take on.  

Please also read through this thread and the mini T2 and KGSSHV build threads for information.   

 

 

Table updated.

 

Edited by mwl168

I'd like to add

1 78xx

1 79xx 

1 mainboard 

to my order (effectively 3 psu sets total)

Thanks!

 

  • Author

Table updated.

 

Construction notes for those getting started to source parts for your builds:

  • R3 and R2 determine the regulated voltage for GRLV. The formula is Vout = (R2 + R3)/R3 * Vref. Vref is the reference voltage of U4 (LT1021).
  • R7, R8, R9, R10 determine the regulated voltage for GRHV. The formula is Vout = ((R8 +R9 + R10)/R7 + 1) * Vref.  Vref is the reference voltage of IC1 (LT1021). You want to keep R8, R9 R10 values close so they have even voltage drop across each of them.  
  • On the PSU Main board, R22 (100K) and C17 (470uf) set up the delay time for HV. The 100k/470uf combination provides a roughly 45 seconds delay. Increase R22 or C17 to increase the delay time. C17 needs to be rated 5VDC or higher.

Also added these construction notes in the first post for ease of access.

Edited by mwl168

I have built a beta 22 and sigma 22 amps from amb. I have also repaired my blue Hawaii several times with live circuits for testing. I am just new to electrostatic amp construction from scratch. So I would love guidance.

Having said that.

I will take a full set for a mini t2 and psu.

Plus a full psu.

2 hours ago, boinger said:

I have built a beta 22 and sigma 22 amps from amb. I have also repaired my blue Hawaii several times with live circuits for testing. I am just new to electrostatic amp construction from scratch. So I would love guidance.

Having said that.

I will take a full set for a mini t2 and psu.

Plus a full psu.

boinger,

You will need to specify which boards and how many.  Also, if you want bare or partially assembled GRHVxxx boards.  That way, there will be no confusion.  

Good luck!  

Edited by Blueman2

1 mini t2 set

4 grhv 

2 each GRLV78xx,

2 GRLV79xx

2 PSU main board

 

That should give me 2 full psu sets correct and 1 mini t2 amp set? 

1 full psu should be good for the kgsshv carbon yes? 

7 minutes ago, boinger said:

1 mini t2 set

4 grhv 

2 each GRLV78xx,

2 GRLV79xx

2 PSU main board

 

That should give me 2 full psu sets correct and 1 mini t2 amp set? 

1 full psu should be good for the kgsshv carbon yes? 

Yup.  Do you want the GRHV partially assembled?  Might be worth it if you have not done a lot of SMD work.  

Hi mwl168,

How the payment is done?

Do you have a PayPal account?

Regards

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