Author Topic: Making square Manhattan pads  (Read 7879 times)

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Offline Howardlong

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Re: Making square Manhattan pads
« Reply #25 on: June 25, 2020, 09:54:00 pm »
I've become a massive fan of Busboards, in particular SP3T-50x50-G and SP3-100x100-G, with 0.05" and 0.1" square pads respectively.

Seconded, for the reasons you give. The only negatives are the cost and having to have them in stock.

The only hard part about laying these out oneself and having a board house fab them is getting them NOT to through plate the holes... I speak from experience!
 

Offline JohnG

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Re: Making square Manhattan pads
« Reply #26 on: June 26, 2020, 01:02:45 pm »
Folks,

Thanks for this discussion. I've used pretty much all of the above at one time or another for various things. I would comment that I do a lot of this for my job, so things that I can buy usually make up for the extra cost due to labor and time savings.

But, Leo's technique was new to me. Since I do power electronics a lot, I can see it being really useful for that. Those big copper areas could be really helpful for pulling heat and current out of some parts. It's perfect for when you don't need a lot of nodes, but most of the nodes you do need should be as much uninterrupted copper as possible.

Cheers,
John
"Reality is that which, when you quit believing in it, doesn't go away." Philip K. Dick (RIP).
 

Offline Quarlo Klobrigney

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Re: Making square Manhattan pads
« Reply #27 on: July 30, 2020, 04:40:08 pm »
Not square, but I use the Harbor Freight ⅜" Spot Weld Cutter 63657 https://www.harborfreight.com/38-in-double-sided-rotary-spot-weld-cutter-63657.html
I can go all the way through and make little islands to glue where I want, or go halfway through on a larger sheet and make attached pads.
Word of warning USE A DRILL PRESS! otherwise serious injury may will result not to mention wrecking the blank PCB.
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Offline cdev

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Re: Making square Manhattan pads
« Reply #28 on: August 02, 2020, 07:54:29 pm »
Is there anything like stripboard (linear signal path oriented protoboard) thats designed to be 50 ohms -impedance controlled PCB ready to slice up and use in a specific subset of RF devices like filters, LNAs mixers etc.?

« Last Edit: August 02, 2020, 10:21:28 pm by cdev »
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Offline tggzzz

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Re: Making square Manhattan pads
« Reply #29 on: August 02, 2020, 08:46:55 pm »
Is there anything like stripboard thats designed to be 50 ohms (or whatever) ? Impedance controlled PCB ready to slice up and use?

Stripboard matches edge mount SMAs pretty well but the impedance is wrong. (and of course you have to add a back side with copper tape)

Still, its better than nothing in a pinch, and works okay for HF.

There used to be Wainwright mini mount stick on 50ohm (and others) strip line, but it hasn't been manufactured inn a while.
« Last Edit: August 02, 2020, 08:57:11 pm by tggzzz »
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Offline Kalvin

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Re: Making square Manhattan pads
« Reply #30 on: August 02, 2020, 10:02:53 pm »
How much would it cost to make a PCB design with square areas of your liking, and ask the PCB manufacturer to cut grooves over the PCB so that the PCB could be snapped easily into separate pad without any powertools. The PCB could be one-sided, and the separated pads would be then glued onto the another PCB functioning as the ground plane. Small pads for point wiring, and even strips for signal traces in order to get approximate match for 50 ohms. PCB thickness could be 0.8mm or 1.6mm, and the pad size and trace width could be designed to give approximate 50 ohm impedance. Any idea about cost for 100mm x 160mm single side board with the snap-grooves for 5mmx5mm pads?
 

Offline TimFox

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Re: Making square Manhattan pads
« Reply #31 on: August 02, 2020, 10:25:22 pm »
Many years ago (before 1980), I bought very nice Manhattan-esque patterns from (if I remember the name correctly) a company called Christiansen Brothers.  The different pieces had useful patterns for transistors, DIPs, TO-5 can ICs, and linear arrays of terminals.  They were easy to cut to length, made on G-10 with tinned copper patterns on the top and a pressure-sensitive adhesive on the bottom (with release paper).  I was able to make respectable circuits at 100 MHz (analog and digital) with leaded parts and these patterns atop single-sided G10 boards.  It was easy to get very short connections from leaded capacitors to the ground plane.
Does anyone know of a commercial source for such pre-made objects?
« Last Edit: August 02, 2020, 10:27:34 pm by TimFox »
 

Offline cdev

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Re: Making square Manhattan pads
« Reply #32 on: August 02, 2020, 10:34:45 pm »
Thanks!



There used to be Wainwright "mini mount" stick on 50ohm (and others) strip line, but it hasn't been manufactured inn a while.

Apparently they were also called "Solder Mount" in the US but were really expensive. The company, Wainwright Filters still exists but no longer makes them.

https://www.wainwright-filters.com/

If I can find some photos I'll post them here.
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Offline TimFox

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Re: Making square Manhattan pads
« Reply #33 on: August 02, 2020, 10:39:53 pm »
The units I remember were not for precision applications, but worked well for DIPs and discretes.
 

Offline rhbTopic starter

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Re: Making square Manhattan pads
« Reply #34 on: August 02, 2020, 11:09:35 pm »
Thomas H. Lee recommends using single sided FR4 with 1/8" copper foil microstrip traces as it's pretty close to 50 ohms and cheap.  There's that and a lot of other pratical prototype and DIY stuff in "Planar Microwave Engineering"  which is the best RF book I've ever read.
This is what he has his students do at Stanford for his RF course which requires designing, building and demonstrating a transceiver.

I plan to test the impedance with my 11801 & SD-24 and post to my TDR porn thread, "Testing RF connectors and cables".

It would really be nice if someone laid out a bunch of  boards with various device footprints and put the board files on github or OSHpark.  I'd order a bunch from JCLPCB for lots of devices.  I've got a few I picked on on ebay.

Another thing that would be really useful is SMD analog filter boards using large parts.

Have Fun!
Reg
 
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Offline cdev

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Re: Making square Manhattan pads
« Reply #35 on: August 02, 2020, 11:32:33 pm »
Thomas H. Lee recommends using single sided FR4 with 1/8" copper foil microstrip traces as it's pretty close to 50 ohms and cheap.  There's that and a lot of other pratical prototype and DIY stuff in "Planar Microwave Engineering"  which is the best RF book I've ever read.
This is what he has his students do at Stanford for his RF course which requires designing, building and demonstrating a transceiver.

I plan to test the impedance with my 11801 & SD-24 and post to my TDR porn thread, "Testing RF connectors and cables".

It would really be nice if someone laid out a bunch of  boards with various device footprints and put the board files on github or OSHpark.  I'd order a bunch from JCLPCB for lots of devices.  I've got a few I picked on on ebay.

Another thing that would be really useful is SMD analog filter boards using large parts.


Have Fun!
Reg



Is it possible to have multiple small PCBs from different designs on OSHpark made at the same time on boards and then snap them apart? because all of what you want is available I am pretty sure, but the way the pricing seems to be done, I need to spend some quality tie figuring out exactly how it works. But basically, I am looking for the exact same things and have collected a bunch of links to people who have put their designs on their site. Cost is important to me, I am trying to minimize the cost of this hobby. That said it should be easy to do. I anticipate using these boards a lot so once something is working I want to make a bunch of them.

I wonder also about thinner FR4 ? thin works best for RF because less loss. (but you need to get the right hardware that allows it, or use copper shims, mild PITA)
« Last Edit: August 02, 2020, 11:36:28 pm by cdev »
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