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Re: Earliest example of Manhattan construction?
Chuck.
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Not sure what the deal is, but I checked a copy of my QRP Classics (with the red cover and published in 1990) and found the article you cited on pp 12-14 and the picture tyou mentioned on page 13.
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William, k6whp
-------------------- "Cheer up, things could get worse. So I cheered up and things got worse." |
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Re: Tayda Electronics and parts, heatsinks, Octopus
That could be, but every order of mine (10-12) has, and always has, shipped from Thailand. I'd love the USA warehouse to be the one, but for the past 6 years, all Thailand, FWIW. --Kirk, NT0Z My book, "Stealth Amateur Radio," is now available from
www.stealthamateur.com and on the Amazon Kindle (soon)
On Wednesday, April 9, 2025 at 02:47:12 PM CDT, davidgeorgerichards via groups.io <djdaverichards@...> wrote:
On Wed, Apr 9, 2025 at 10:02 AM, Daniel KK4MRN wrote:
Question - good place to get NG0 / CG0 good quality capacitors for VFO and filters right now?Hi Daniel -? ?
Like many of us, I'm often on the lookout for good deals on parts, and even not so great deals if it's a much sought-after part that is hard to find. However, I'm beginning to question the wisdom of not always putting quality first with some of my previous purchases. I have a small stash of NPO's here (I do like the older big disc ceramic NPO's with stout leads and the black band across the top!) However, going forward, I plan to begin building up my stock of NPO/C0G caps from Mouser. I have confidence in the quality of their parts. For example, 270pF C0G MLCC's made by TDK are $0.21 apiece, but drop to $0.129 if you buy 10. If you're feeling ambitious and want to buy 100, the price drops even more, to $0.086 apiece - that's just $8.60 for 100 quality C0G caps. Sure, you might get NPO's cheaper somewhere else, but can you be sure of the quality? I imagine DigiKey have similar prices; it's just that Mouser is my main supplier of choice, with Tayda second, and other suppliers on a very occasional basis, as needs dictate. Dan's is fun to order from, for that "1970's ad in a magazine mail order" experience. You write or type out your order on a piece of paper, mail it to him with a check - and wait for a couple of weeks. It's just like being a kid all over again!
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Dave
AA7EE
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Re: Tayda Electronics and parts, heatsinks, Octopus
I have had constantly good luck buying parts from Tayda, but they do not have a USA warehouse. All from Thailand via Hong Kong. Great company. Not sure how tariffs will affect them, so I just received a large order! Regards, --Kirk, NT0Z My book, "Stealth Amateur Radio," is now available from
www.stealthamateur.com and on the Amazon Kindle (soon)
On Wednesday, April 9, 2025 at 12:02:36 PM CDT, Daniel KK4MRN via groups.io <daniel-kk4mrn.skipper529@...> wrote:
Hey,
I was thinking of getting some parts from Tayda Electronics.? I think they have a warehouse also in the US but not sure if all the parts I need are there.
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I think some of you have gotten those D882 transistors before and had good luck with them?
US $ 0.14 each.
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And get some heat sinks for the D882 transistors above but also those 2SC5706 I got from kits and parts.? But not sure about the packaging of either of those.? So, not sure what heat sinks where work for either of them.
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Some trimmer capacitors too. I think Steve buys his from there and they work for him.
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Question - good place to get NG0 / CG0 good quality capacitors for VFO and filters right now?
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Sure, I got a value boxes of capacitors off Amazon and I checked them and they seem to be in range of their stated tolerance.? But when it comes to a VFO and filters, I think better quality capacitors are needed.
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73 Daniel KK4MRN
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AA7EE QSO and SolderSmoke DC Receiver
Did get two chances to work Dave, AA7EE, on 17m.? He called me once and I called him
once.? Time of day when you are 599 and 15secs later you are gone.? Nil.? Nada.? Zilch. Thanks Dave. Attached is the audio amp board about ready to go.? Not as neat as Daves work, but it is sure fun to build.? I had to start this project his morning and I'll have it done by sunset. Using the same size board, but sheared into 3 parts, I'll build the other three sections.? Then the plan is to attach them to the back of this board, thus coming up with what may be the smallest form factor or all. I'm not in the same league as Dave, AA7EE, and Jim, K8IQY, but I do enjoy working the technique.? I recommend it for anyone who has a small project to learn with.? Just do it. The Manhattan Madness continues. FYI -- chuck adams, aa7fo QRP WAS 17m started Apr 2, 2025 WAS-17 QRP --> TX,FL,SC,GA,OK,AR,KS,AL,AZ,MN PA,CA,CO,WI,NE,ID,IL,NC DXCC W,VE,JA,PY |
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2N2/20 Scratch-Build - Progress So Far
A few weeks ago, I started building a 2N2/20 from a kit and ran into a problem with what appears to be a lack of gain somewhere in the receiver. I couldn't figure out where the problem lay. As a result, I thought that if I scratch-built a 2N2/20 using the same schematic as the Norcal kit version, I'd have a working unit with which to make measurements and comparisons. I've been wanting to scratch-build a 2N2 rig for years now anyway, so this was a good opportunity. I wasn't going to post anything until it was completely finished and fully operational, but I'm running into a small snag, so thought I'd share my progress so far and share the info, in case anyone can shed some light.
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The picture shows the state of the build as of 2 days ago. Everything seems to be working normally, based on simple tests touching wire antennas to the inputs of the various stages, and listening to the sounds from the speaker. The only abnormality is a slight instability in the IF amp stage immediately following the main 4-pole crystal filter. I have circled this stage in the second picture and also in the schematic. It manifests itself as a scratchy noise in the speaker. When I bring a finger in close proximity to the toroidal transformer T11, or either the 100 ohm resistor R36 or 01.?F coupling capacitor C46 that feed the input of the MPSH10 transistor, the noise stops, but the gain of the receiver strip is not affected. It just kills what sounds like some kind of parasitic oscillation. I replaced the 0.1?F cap C46, suspecting a noisy component, but that wasn't it. I may end up rebuilding the stage. We'll see.
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Anyway, the debugging process is engaging, and it gives me something to do when I get up in the morning.
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In other news, I've had the pleasure of two very brief QSO's with Chuck on 17M in the last few days. QSB was working against us, but I'm happy with brief exchanges anyway. Chuck and I are only about 600 miles apart, so it's not too challenging a haul for a couple of QRP'ers.
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Dave
AA7EE
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Dave
AA7EE
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Re: Help aligning VFO (Ozark Patrol regen)
I've observed the same thing. The ability to do accurate L & C measurements can make trimmers unnecessary. Also, when you're close but not exactly there, you can use LTspice or other simulation software to see if you're close enough. 73 Nick, WA5BDU On Sun, Apr 6, 2025 at 7:42?PM John RC via <amradebc=[email protected]> wrote:
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Re: The end of inexpensive printed circuit boards and parts
Excellent sentiments all the way around! That I stocked up on kits, pcb material, parts and stuff before I retired BEFORE I RETIRED is kinda gladdening.?
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William, k6whp -------------------- "Cheer up, things could get worse. So I cheered up and things got worse." |
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Manhattan Layout Pad Template
For those of you wanting to do Manhattan construction.? You want to
plan ahead as much as possible.? And not spend a lot of time being an artist. I found that if I use a membership card for a gated community that has the lanyard hole already in it, it works to easily place and draw pads on paper with a pen or pencil. Possibly use an expired credit card and use the hole punch and make the hole sizes you need.? Punch through the magnetic strip and card numbers for security. And I just draw a from pad to pad with a centered space with the part number, i.e. R1, and I don't have to spend a lot of time drawing outlines for resistors, caps, etc.? Does not have to be to scale and you adjust as you build. dit dit -- chuck adams, aa7fo QRP WAS 17m started Apr 2, 2025 WAS-17 QRP --> TX,FL,SC,GA,OK,AR,KS,AL,AZ,MN PA,CA,CO,WI,NE DXCC W,VE,JA,PY |
k6whp
Kirk Kleinschmidt, NT0Z
Nick Kennedy
