[TowerTalk] I.C.E. Vendors

[Grant Saviers]

For those not familiar with ExpressPCB, here is the deal -

three double sided plated thru hole boards 2.5" x 3.8"  delivered in 
about 3-4 days for $51.
free layout and schematic entry tools, decent library of digital parts 
and pad layouts
larger boards, 4 layer, solder mask, silk screening available for more $

I've used them for a number of projects and the quality is very good and 
the tools are easy to use.  SMT or thru hole (various drill sizes are 
available) is no problem and adding holes for cut/break lines is easy as 
long as you stay under the hole limit (about 300 per board) for the $51 
special.

expresspcb.com

Grant KZ1W

On 4/13/2011 3:28 PM, Fred Spinner wrote:
> Manhattan style is where you take small pieces of PCB (little squares or
> whatever) and hot-glue (or epoxy or whatever) them to a bigger piece of PCB
> or other surface, typically a ground plane of some sort, to make a
> multi-layer stack (like a "skyscraper" or "manhattan").  I personally don't
> like building that way.
>
> http://www.k8iqy.com/construction/ConstructionMethods.htm
>
> Seems to have a good explanation.  I prefer a dremel and a small router bit
> and hand etching a board that way instead.
>
> Fred W0FMS
>
> On Wed, Apr 13, 2011 at 11:41 AM, Stan Labinsky Jr.
> <wa2puq at frontiernet.net>wrote:
>
>> Fred, "Manhattan" style... I missed that one in class... care to explain?
>>
>> Stan
>>
>> ----- Original Message ----- From: "Fred Spinner"<fred.spinner at gmail.com>
>> To:<towertalk at contesting.com>
>> Sent: Wednesday, April 13, 2011 11:03 AM
>>
>> Subject: Re: [TowerTalk] I.C.E. Vendors
>>
>>
>>    There is nothing to stop anyone from hacking a small part of a PCB,
>>> soldering the chip on to it, soldering leads on to it and making a leaded
>>> part out of a SMT part.  this is handy if retrofitting an existing etched
>>> board design.
>>>
>>> But for something like a filter, a Dremel etched PCB or "manhattan" style
>>> construction with SMT parts would be no more difficult than building
>>> point-to-point with leads-- it would probably be easier and the end result
>>> would work better.
>>>
>>> But yeah, if you can get the values in SMT, you can always MAKE leaded
>>> parts
>>> out of them.  Doing that is a completely valid substitution for an
>>> one-off.
>>>
>>> Fred W0FMS
>>>
>>> On Sat, Apr 9, 2011 at 10:44 AM, Dan Zimmerman N3OX<n3ox at n3ox.net>
>>> wrote:
>>>
>>> You can get every necessary value for the BC band-reject filter  from
>>>> Mouser
>>>> (and I'm sure, Digikey) in 100V 5% ceramic surface mount type.  I forgot
>>>> to
>>>> check if all were available in C0G, but I know some were, and I think all
>>>> are... it's very standard and the correct choice for RF applications.
>>>>   Prices are low... 40 to 60 cents in Qty. 1 for some spot checks.
>>>>
>>>> > From what I can find the HF Q of the standard chip caps at least
>>>>> 600-1000
>>>> (dissipation factor of at most 0.0015 is quoted many places, which is
>>>> Q=667,
>>>> some data sheets say Q>1000).  And I think all this is probably more or
>>>> less
>>>> the same for C0G ceramic disks vs. C0G ceramic chips if dielectric
>>>> dissipation is at fault.
>>>>
>>>> Intuition tells me that anything a leaded ceramic disc cap could do, a
>>>> surface mount chip cap can do better with the exception of handling
>>>> continuous RF currents and dissipating the resulting heat... not because
>>>> they're more lossy (they may be less) but because they are physically
>>>> smaller.  For receiving filters this should not be an issue.  For things
>>>> like QRP low pass/bandpass filters, etc, they might.  (For QRO filters
>>>> you'd
>>>> probably be looking for mica caps anyway.  But even there, surface  mount
>>>> versions seem to be more available and a bit cheaper ($4-$5 in Qty.1) at
>>>> least in new parts )
>>>>
>>>> It's not too hard to use surface-mount chip caps in dead-bug construction
>>>> as
>>>> long as you have a decent pair of tweezers.
>>>>
>>>> 73
>>>> Dan
>>>> _______________________________________________
>>>>
>>>>
>>>>
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>>>
>>>
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>>
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