Tom Taylor did a couple batches and distributed the boards, for which he
deserves a round of kudos, but he isn't in a position to do it again. He
had suggested that someone was giving thought to the project, but I don't
know if that is coming to fruition.
Any word on this? I need a blank board myself, btw.
Me too, Chip. Bad part is I had one, collected all
the parts to do the build and now I can't find it:
Not in envelope it arrived in nor the drawer that
and the components are in -- so I fear it may have
somehow been trashed.
On 5/25/14, 5:48 AM, Chip Stratton wrote:
> Anybody working on another batch of the Modular Accessory Board for the K2
> as documented here:
> http://www.genebitsystems.com/david/K2MiscAccessoryBoard/index.htm >
> Tom Taylor did a couple batches and distributed the boards, for which he
> deserves a round of kudos, but he isn't in a position to do it again. He
> had suggested that someone was giving thought to the project, but I don't
> know if that is coming to fruition.
> Any word on this? I need a blank board myself, btw.
I'm willing to place an order for these boards under these conditions:
These boards come 3 to a sheet from ExpressPC boards. You have to cut the
three boards out with a shear to use them, then there are some other minor
mods to each board as documented in the PDF I linked to above.
The "per order" setup fee for this 4 layer board is very high at $276
minimum. If I order 6 sheets the order total will be $336. If 5 other
people will each commit to buy a sheet of 3 boards for $56 I'll place the
order. Each person would be responsible for doing with those three boards
what they please, be that sell to friends, list members, or whatever.
I'm not optimistic that enough will express interest, but its worth a shot.
I emailed Tom Taylor's contact over a week ago but haven't heard back, so
don't know whether or not Doug will be following through with those plans.
I'd just noticed the MAB on the LA3ZA modifications page and was doing
initial research, although my feeling is that the component sourcing
costs are going to be too high to justify, especially if one has to buy
the extender and pay customs clearance fees on it as well as multiple
lots of international shipping (Mouser is OK if one can bulk up the
order with other things that only they can supply, as they have special
arrangements to pay UK taxes up front).
I don't have the capabilities for cutting up the boards and I'm not sure
if I could sell them on anyway (also there may also be consequences of
becoming a manufacturer in terms of legal responsibilities). However, I
did have a look at the ExpressPCB site and I noted:
1) they advise against cutting up four layer boards because of the risk
of shorting power and ground planes. That suggests yields from the
separation process could be low.
2) they do do large runs much more cheaply, so creating industry
standard CAD files may not be necessary.
3) it is difficult to understand why the setup costs are so high and I
wonder why they can't give a discount on re-orders from the same CAD file.
Owner K2 06123
On 27/05/14 19:42, Dave KW4M wrote:
> Each panel contains three MAB boards. So the cost per MAB board would be
> I used a shear to cut out the individual boards. I believe Tom used a band
> If there was sufficient demand it would make sense to convert the layout to
> use industry-standard Gerbers and place a larger order from a regular board
> house. The cost would then be very low.
The project is at that awkward point where more than a few prototypes are desired but likely not enough to enable a reasonably priced production run. Ideally someone with resources beyond mine would want to pick it up at some point if the numbers are there to justify it.
ExpressPCB's advice against cutting four layer boards was noted and considered. To reduce the possibility of shorts, the internal plane layers were designed to have voids in the areas where cuts are to be made. In my estimation, electrical shorts due to cutting the boards is not an issue.
I know not what a MAB board is, but I bought pcb's from ExpressPCB
and cut them using a dremel cutoff wheel run against a metal ruler
to keep a straight line. Comes out very neat. The clue is to allow
some space on the board for cutting. For little projects this works
I made TR boards with RF sensing ckt as example and my five band LP
filter for the amplifiers I built. Those were large boards (5.5x9
inch) so cutting was required.
Thanks, Ed. Sounds like good advice -- and I have that tool :-)
On 5/28/2014 11:59 AM, Edward R Cole wrote:
> I know not what a MAB board is, but I bought pcb's from ExpressPCB and
> cut them using a dremel cutoff wheel run against a metal ruler to
> keep a straight line. Comes out very neat. The clue is to allow some
> space on the board for cutting. For little projects this works out
> I made TR boards with RF sensing ckt as example and my five band LP
> filter for the amplifiers I built. Those were large boards (5.5x9
> inch) so cutting was required.
> 73, Ed - KL7UW