[GROUP BUY] G9 in 51X format (CLOSED, ALL STOCK GONE)

[Mike D]

Just paid for 2, thanks a lot

 

[tonycamp]

Hi Rodney, quick Q, any idea of total build cost on this? I'm trying to figure out how much $ i've been blindly committing to lately ;D

 

[mulletchuck]

Did I spy some SMD components on the HV converter??

 

[gemini86]

Yes, one soic 8, a diode an inductor and a resistor. All really easy to solder by hand. This was the only way to get it all to fit.

 

[wolan42]

Hello Rodney,

paypal send for 2 boards.

Thanx

Andreas

 

[Graph]

Just paid for one + shipping

It would be amazing to use the converter for other diy projects, like a pultec, i think it would be much easier. Let us know about frontpanel.

 

[mulletchuck]

It would be amazing to use the converter for other diy projects, like a pultec, i think it would be much easier. Let us know about frontpanel.

how about an LA2A-51X, since Ruckus328 never finished his...

 

[Graph]

It would be amazing to use the converter for other diy projects, like a pultec, i think it would be much easier. Let us know about frontpanel.

how about an LA2A-51X, since Ruckus328 never finished his...

That would be great too.

One question, how much current does this build use or needs? Will it have enought current for a standart 51x build from the PSU?

 

[gemini86]

It would be amazing to use the converter for other diy projects, like a pultec, i think it would be much easier. Let us know about frontpanel.

how about an LA2A-51X, since Ruckus328 never finished his...

That would be great too.

One question, how much current does this build use or needs? Will it have enought current for a standart 51x build from the PSU?

I thought ruckus was still working on his? He was talking about developing a flyback converter design, which is a bit more complicated. I had thought about using that topology, but for a two bottle preamp, really not needed. If you have the time and cash to spend on R&D, a simple boost converter can be over 90% efficient.

I made the HV converter a separate board for three reasons. 1- shielding from signal lines on the bottom layer of the main board. There's a copper ground plane between the converter and the signals on the bottom of the board. 2- repair-ability. You can stick the HV converter board onto a hot plate and remove/replace the SMD devices if needed. If it were integral to the main board, this would not be possible. 3- I wanted it to be a separate module, which could be swapped out with an upgraded version should one come around. After this project rolls out, I'll be working on a new converter that will be more stable/efficient with higher output capacity. The tech guy at Maxim IC has given me a good starting point, but it will take more time, more money and, oh, also lots of time.

The converter I have, as tested, uses max 140mA on the +24V rail. The tubes use the -24V rail @ 150mA (this is the maximum for that rail/per rack space) and the relays operate on +16V rail. There are only 2 so that rail is loaded light, and the -16V rail is unused. (there's also the +48v rail, running through standard 6k81 resistors for phantom)

One thing to consider with all these 500 modules is that everything has to fit perfectly in order for it to go into a rack! SO much time is used up just making sure everything is lining up, making adjustments, checking datasheets for front switches, connectors, etc. Waiting for stuff to come from mouser is torture.

PS I've not yet heard from the fabrication house about the brackets...

 

[DomiStenz]

I payed for two 

 

[mulletchuck]

sorry for the tangent;  ruckus never finished it. however, he did post about an 1176A/D clone he'll be releasing in january in his build thread.  that's probably why he never finished the LA2A-51X.  Gemini, we need you to take over!!!  lolol :-D

 

[Marc Duchesne]

Money sent for my 2 G9 boards...
Please confirm reception.

Thanks a lot for this !!!

 

[gemini86]

sorry for the tangent;  ruckus never finished it. however, he did post about an 1176A/D clone he'll be releasing in january in his build thread.  that's probably why he never finished the LA2A-51X.  Gemini, we need you to take over!!!  lolol :-D

I bet he'll get back to it and have it finished before i could even get a working prototype built. It's his baby, give him time. I have some other tube projects in store for you guys.

 

[bkbirge]

PS - To everyone who wants a face-plate/metalwork kit:

What do you think about the faceplate styling??? If we can all agree on the design, I can order the whole lot from FPE and get a discount. If we order 10 pieces, the price drops from 31.35 each to 25.08 each, and I can ship them out with the PCBs to consolidate shipping.

Mark me down for 6 of 'em. I think you'll have no problem getting to the batch size discount.

 

[gemini86]

PS - To everyone who wants a face-plate/metalwork kit:

What do you think about the faceplate styling??? If we can all agree on the design, I can order the whole lot from FPE and get a discount. If we order 10 pieces, the price drops from 31.35 each to 25.08 each, and I can ship them out with the PCBs to consolidate shipping.

Mark me down for 6 of 'em. I think you'll have no problem getting to the batch size discount.

I've been working out trying to get them cheaper. Chae gave me a quote for laser marked panels, now I'm trying to figure out drilling. (hint hint, chae) They will probably be much cheaper and look better.

 

[speakerface]

Just sent payment for 2.  Also interested in front panel (basic design is good with me) as well as L-bracket, etc.  Thanks much. 

 

[gemini86]

Hi Rodney, quick Q, any idea of total build cost on this? I'm trying to figure out how much $ i've been blindly committing to lately ;D

Sorry, somehow missed this Q...

I'll figure that out when I get the BOM together, i'll likely be ordering components for a full build so I can take pics for a build thread. If I remember correctly (and it's hard to say, since I had ordered a couple wrong parts/missed some things etc.) small components and switches, etc from mouser were like 30 bucks. Then it's up to your tube and transformer selection.

Money sent for my 2 G9 boards...
Please confirm reception.

Thanks a lot for this !!!

Got your payment, thanks!

 

[gemini86]

You know, after looking through all these options, I'm beginning to thing that PCB front panels makes the most sense here.

.125" thick fr4, copper 1oz copper on both sides for shielding, silkscreened markings. I can get them for less than 10 bucks each, depending on quantity. The manufacturer has assured me that the silkscreen quality will be top notch (they've done a good job before).

What do we think?

Still working on brackets.

 

[okgb]

10 Bux , = No brainer  , I'm in for two , and actually sounds novel
lighter ..............

 

[tonycamp]

Igor did that on his f76, looks great, i'm down widit 8)