Re: When PCB's are too expensive, and you're out of copper boards.
Never:
<>? in the USA
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On 4/4/25 10:31, Ryan Flowers via groups.io wrote:
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Ryan Flowers - W7RLF
<>
W7RLF Prototyping Boards <>
MiscDotGeek YouTube Channel <>
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chuck adams, aa7fo
WAS-17 QRP --> TX,FL,SC,GA
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Re: Manhattan Noise Bridge
OK.? R2, R4, R6??? 22K 1/4W resistors
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BOM:
R1,R3,R5? 1.2K? 1/4W resistors? (not too critical)
R7??????? 680ohms? 1/4W resistor?? (drives the final stage harder)
C1,C2,C3,C4? 10nF mono or disc caps? (.01uF if you prefer labeled 104)
D1??????? 6.8V?? 1/2W zener diode
Q1,Q2,Q3? 2N2222, 2N3904 or 2N4401 NPN transistors? (just about anything)
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chuck adams, aa7fo
WAS-17 QRP --> TX,FL,SC,GA
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When PCB's are too expensive, and you're out of copper boards.
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For some things that I test on a receiver, I find the following to be
of great use around the lab.? It uses the fact that a zener diode will
generate a lot of random noise.? Let's not nit the pink vs gaussian vs
exponential vs white vs .... types of noise.
1.? Use it at the build of each stage in a receiver, if you start with
the audio amp first as in the series of videos I'm doing.
2.? Use it after a build or even for working rigs to test the IF
filter.? Requires an audio analysis computer program that shows
a spectrum plot.? I'm currently looking for an ARM based SBC
program since most non-free software binaries run only on Intel/AMD
base computers.? Open source would be great.
3.? Irritate the neighbors.
Attached:
0084.jpg? original prototype using on two stages on PCB done toner transfer
Screenshot...? showing Manhattan layout drawn by C program I wrote
?????????????? I will come back and change the call sign.? :-)
Schematic lost in the dark caves of large SSDs and to be recreated
at some later date.? But you can reverse engineer the layout to a
schematic.? You've been there and done that many times before.
BOM:
R1,R3,R5? 1.2K? 1/4W resistors? (not too critical)
R7??????? 680ohms? 1/4W resistor?? (drives the final stage harder)
C1,C2,C3,C4? 10nF mono or disc caps? (.01uF if you prefer labeled 104)
D1??????? 6.8V?? 1/2W zener diode
Q1,Q2,Q3? 2N2222, 2N3904 or 2N4401 NPN transistors? (just about anything)
The part values are not critical.? You can use what you have in the
parts depot in the closet and it's more fun to experiment.
I think I got everything.? Exercise for the student(s).
This critter will be used pretty soon in the ongoing videos and
there after many times.
FYI
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chuck adams, aa7fo
WAS-17 QRP --> TX,FL,SC,GA
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I designed my own in black & white, got my daughter to draw a simple illustration, and laser-printed them onto card-stock. QRP, homebrew QSL cards!
73 de Todd W2TEF
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Re: The end of inexpensive printed circuit boards and parts
I'm quite aware of the market turmoil. Not saying anything more about as that's off-topic and it can't be solved here ;)
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Solder has gotten very expensive? ~$40-$50/lb and Manhatten uses a lot of it!.?
That's one reason? why I went with SMT construction.
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Steve
WA6ZFT
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Re: The end of inexpensive printed circuit boards and parts
On 4/4/25 09:49, Michael Maiorana via groups.io wrote: I think OSHPark is at $5 per square inch?for three boards. So 3 100x100mm boards would be $80, not including shipping. Those boards from JLCPCB would have been $5 for 5 of them.
If you think the removal of the de-minimis exemption is sad, go have a look at your 401k.
Looks like even more reason to go "Manhattan" style with Chuck!
73
Mike M.? KU4QO I've been spending like crazy the last month to restock the new lab. You've seen the photos of the transistor collection, caps, resistors, etc. I'm glad I spent the pocket change. I've packages incoming through the airport as we speak.? And the thing that scares me is that I have a metal brake due Apr 23 to May 8th!! So, you are telling me that we all have to get our stuff together PDQ or we're all going to be looking for a new hobby? You think the ebay vendors are going to ship faster? Geez.? I've got to release the adc-40 transceiver board by first of next week.? The pressure is on. chuck, aa7fo WAS-17 QRP --> TX,FL,SC,GA
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Re: The end of inexpensive printed circuit boards and parts
I think OSHPark is at $5 per square inch?for three boards. So 3 100x100mm boards would be $80, not including shipping. Those boards from JLCPCB would have been $5 for 5 of them.?
If you think the removal of the de-minimis exemption is sad, go have a look at your 401k.
Looks like even more reason to go "Manhattan" style with Chuck!
73? Mike M.? KU4QO
If you need 3 PCBs, OSHPark special including USPS shipping is $10. But I don't see why they would keep this price when the competition goes away.
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73, Mike AF7KR
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Re: The end of inexpensive printed circuit boards and parts
If you need 3 PCBs, OSHPark special including USPS shipping is $10. But I don't see why they would keep this price when the competition goes away.
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73, Mike AF7KR
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The end of inexpensive printed circuit boards and parts
As some of you may be aware, the president has eliminated the de-minimis tariff exemption for China and Hong Kong.
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Under the executive order, packages coming through the international postal network will either be subject to a fee of 30 percent of the value of the goods, or $25, rising to $50 in June. Whichever is greater.
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This means the duty will be $25.00 for packages from these countries from May 2, 2025 and $50.00 from June 2, 2025 Onwards.
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Relevant news article:
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This means no more inexpensive printed circuit boards from Chinese manufacturers such as JLCPCB and PCBWAY and no more inexpensive parts from LCSC or Aliexpress.
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The only way we'll get inexpensive circuit board fabrication in the future is if some US-based circuit board manufacturer decides that the hobby market is big enough to service.
Of course JLCPCB et. al could open a plant in another country, but that would be a risky proposition. The de-minimis tariff exemption could be eliminated from other countries in the future.
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So if you have any PCB designs? ready or parts needs to submit it would be prudent to submit them soon to take advantage of the low costs before the de-minimis tariff ends.
You also should make sure that your design ships out before the middle of April so that it doesn't get held in customs for duty payment.
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If this de-minimis exemption isn't relaxed by the president, then?guess I'm going to have to find something else to occupy my time for the near term as these increases are going to make homebrewing using fabricated PCB's too expensive.
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Steve
WA6ZFT
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Hi Chuck,
I designed my own and had them printed up via Vista Print. Not sure if that's exactly what you're looking for, but it worked out well for me.
73,
Max? KJ4WNA
On Fri, Apr 4, 2025 at 10:16?AM chuck adams via <chuck.adams.phd= [email protected]> wrote: Worked a critter yesterday and he said he was sending a QSL card to
confirm QSO.
Went looking for online source/printer and not having any luck since we lost
W4MPY.? Any ideas?
tnx
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chuck adams, aa7fo
WAS-17 QRP --> TX,FL,SC,GA
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Worked a critter yesterday and he said he was sending a QSL card to confirm QSO.
Went looking for online source/printer and not having any luck since we lost
W4MPY.? Any ideas?
tnx
--
chuck adams, aa7fo
WAS-17 QRP --> TX,FL,SC,GA
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Re: uPDCR Phasing SSB Receiver
Looks great. How's the interesting project coming?
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I agree with Doug. I haven't seen Chuck's videos until they were mentioned in this thread. I watched a little earlier today while taking a break from work, and it was pretty great, and earned an instant subscription from me.
Max KJ4WNA
Chuck, great video.? I really like how you do them.? Guys, you need to watch all of Chuck's videos.? ?They are a treasure trove of information.?
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Doug, KI6DS
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Chuck, great video.? I really like how you do them.? Guys, you need to watch all of Chuck's videos.? ?They are a treasure trove of information.?
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Doug, KI6DS
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On Thu, Apr 3, 2025 at 06:40 AM, chuck adams wrote:
Can I go back and change it?
Apparently..
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https://www.youtube.com/watch?v=LJLHcFexLdo
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William, k6whp
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"Cheer up, things could get worse. So I cheered up and things got worse."
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Encyclopedia of Electronics Vols 1-6
Gang,
Probably, most of you know about the Graf series of
books titled "Encyclopedia of Electronics" with volumes
1 through 6.? Just about anything you are looking for
may be in there.? Crystal oscillators to sirens.
Amplifiers of all types and the list goes on.
All six volumes are on archive.org and are downloadable.
If you are looking for something to do, then you should
consider spending the next three or four months reading
these in your spare time.? You wont have any spare time
when you start.? Been there.? Done that.
Or read them in place on the web.
FYI
chuck, aa7fo
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I chose the for kids option at the time because it looked good.
I'm not a professional and haven't done the research as to the
advantages and disadvantages.? Can I go back and change it?
thanks,
chuck, aa7fo
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On 4/3/25 04:00, Karl Heinz Kremer - K5KHK via groups.io wrote: Hi Chuck,
welcome back to YouTube! It looks like you¡¯ve selected that your videos are made for kids - this turns off some very useful features like getting notifications when you post a video. You may want to reconsider this - we are all adults :)
Karl Heinz - K5KHK
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Hi Chuck,
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welcome back to YouTube! It looks like you¡¯ve selected that your videos are made for kids - this turns off some very useful features like getting notifications when you post a video. You may want to reconsider this - we are all adults :)?
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Karl Heinz - K5KHK
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Here is updated from several viewers.
Check one more time for effect.
The X1 in the transmitter will be renamed X5.? The original
was named X1 due to being on the one page for the transmitter.
thanks in advance,
chuck, aa7fo
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Todd W2TEF
hwstar
k6whp