KGST board sets available

[mwl168]

Hi:

 

I just placed an order to have 10 sets of KGST boards made. A few of them are already spoken for but I should have 5 sets available to those interested. Here are some details:

 

1. The amp board is KGST6S4CASCODE (120mm x 135mm), the PSU is KGBHULTRAMINPSV4 (105mm x 134mm). 

 

2. The boards are all 2mm thickness, 2oz copper, green silkscreen with white lettering. I wanted the thicker board that can better sustain the mounting and dismounting of the tubes.

 

3. I am using a PCB fab house in Taiwan which was recommended to me but I have no prior experience with them.

 

4. JimL has traced the cascode CCS part of the KGST6S4CASCODE board (see KGST thread), I traced the rest of the board by comparing it to the KGSTMINV03 board. However, to my knowledge, no one has built the KGST6S4CASCODE board yet so it should be considered un-proven. 

 

5. The cost for each board set ( 2 amp PCB and 1 PSU PCB) is $50 USD plus applicable PayPal fee and shipping cost from me to you.

 

6. I may potentially have one set with 1.6mm thick, 2oz copper KGSSHVPSMINIFINALSTN9360 PSU board available but cannot promise.

 

Please respond to this thread if you are interested. If there are more interests than can be accommodated, inclusion will be based on a first-come-first-serve basis (FCFS).

 

I will PM those respond their interest with my PayPal account and further logistic information.

 

please let me know if you have questions.

 

Thanks!

Edited December 6, 2015 by mwl168

[nopants]

I'm interested in 1 set

[eggil]

I'll take one set too. Txs.

Edited April 29, 2015 by eggil

[insanity]

I am interested in a set too. thx

[DefQon]

Payment made for mine. 

[b0bb]

I would like a set.

 

Thanks

[samsie]

I would like a set.  Please inform me the method of payment and the total amount.

 

Sam

[Rodeodave]

I'm interested in a set! Hope that there's still one up for grabs.

[mwl168]

The PCB boards arrived today. I'll post photo tomorrow and start shipping them out.

Hi Rodeodave:

Sorry, but all the boards I ordered are spoken for a few weeks ago.

Best!

[mwl168]

Here is a photo as promised.

 

 

[FJC]

Anyone have a set of the cascode boards for sell?

 

Fran

[mwl168]

I have been informed of a few PCB issues from a few GB participants in the last few weeks and want to bring this information to your attention. Please do let me know if you run into similar issues or other issues which you believe are related to the PCB. I like to file a complaint with the manufacture with a summary of the issues and get their response. This manufacture (EMB PCB) was recommended to me by a forum member and this is the first time I’ve used them.

I should also note that my order with EMB PCB includes other PCBs other than the KGST ones. Here is a summary of the issues that have been reported to me but they are not specific to the KGST boards:

1. One report of an entire island of solder came off during de-soldering with solder wick

2. Two reports where a few through holes were either too small or over-plated making inserting the parts difficult

3. One report of a couple of spots on the PCB where the copper is visible through the solder-mask maybe the solder-mask didn't take properly

4. One report where one corner of the silkscreen appears smudged

5. One report where 2 through holes were completely plated an need to be drilled open.

For issue #2, I tried inserting parts in the same spots on the board I have and did not encounter problem. So this appears to be a QA consistency issue.

I should also mention that sorenb who encountered the problem with the solder island coming off has built a working KGST amp with the boards he got from this GB. However, the solder island should not have come off so easily.

Again, please let me know if you run into issues or if I have missed issues that you have reported to me. I apologize for these problems and will share with you what response I receive from the manufacture when I file the complaint.

Thanks!

Edited June 30, 2015 by mwl168

[DefQon]

Guess I'll need to check out my boards for anomalies. Will report back.

[mwl168]

As promised, I want to share the two responses I received from EMB PCB after I notified them of the PCB quality issues that were reported to me (see posting # 12). For space reason, I did not post my complaint to EMB but it's basically a copy-and-paste of posting 12 for the most part.

 

While I don't expect a manufacturer to be perfect, I do expect a manufacturer to be sincere and proactive in addressing issues arise. I do not plan to request quotes from this manufacture for the HV Carbon GB based on our collective experience. Please feel free to share your thoughts. Thanks! 

 

 

"Hi Michael,

 

Here are our responses to your questions:

 

1. The reason of solder came off from the board while de-soldering could be the overheated soldering iron or repeatedly soldering. 

2. Please advise which holes you mentioned are too-small or over-plated, we manufacture boards based on your gerber files, and the through hole tolerance is +-0.08mm, so if your hole designed exactly 100% fit to the parts, the tolerance might cause the problem. 

3. & 4. The friction between boards during production or packing might cause the visible copper on the boards, as well as the silkscreen smudged. But as long as these issues don't bring any malfunction to the boards, we'll count as qualified boards. 

5. Please clarify which holes you need are NPTH but not PTH. The default of manufacture is PTH, unless you have specially mentioned (either in the gerber files or emails) which holes you need them to be NPTH, the holes will be all plated.

 

Please refer to the attached file of our trading terms which I have send to you in my first email. 

About your question #3&4, please see item 13; also, please kindly read item 14-15, we have certain time restricted toward the customer complain. We checked the record that your package was received on 5/27, but now it's already 7/15, almost one and half month passed, so now we could only help and solve your doubts, to prevent any possible caused misunderstanding maybe in next business.

 

Thanks,"

 

"Dear Michael,

 

We believe the professional skills that your person have, but there are still some possible reasons caused that solder came off during the soldering and de-soldering process, I know our quality would become the first suspect you have, however, the SMT line we have is also using the boards we made, and this kind of question never happened before.    

Also, other customers' boards which we manufacture at the same time(same production line) as yours are all fine, we didn't receive any complain letter about this issue.  

 

As to the holes, please help to provide photos showing exactly which holes on which boards are not made base on your gerber designed, and you can attach pictures showing parts that solder came off as well . Otherwise we cannot understand clearly the questions you have now. We'll do our best to help you clarify where the problems come from, even though this order is already passed the warranty time.  

 

We have faith in our quality and price, but I know sometimes there might be some mistake during the production, that's why we didn't escape from your first complain email. We're sorry to hear that these boards didn't fit to your expectation. But now all we can do is to examine the photos and try our best to trace back and clarify all these problems.

 

Thanks,"

[Laowei]

Thanks in advance for not sourcing the Carbon PCBs from these guys.