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Can someone please help me to learn how to crimp JST XH connectors? I have watched over 2 dozen youtube videos that claim to be for JST but are actually for DuPont connectors which are longer than XH. The only video that even gave me a clue that the jaws could not be any wider than 4mm was this one: https://www.youtube.com/watch?v=D1ErLvXlOTs The XH connector is only about 7mm long and only 4mm can be under the die. The problem I am having is that I bought a "micro crimper": https://www.amazon.com/dp/B078WPT5M1 but have the hardest time getting the pin into the die. The micro version seems to be just a bit too small (groove) to get the pin in. So with all that said, can someone help me learn how to do these connectors? Thank you. Jim Pruitt WA7DUY

Hi Chuck, Can I make a recommendation for your Manhattan Construction Classes? Can you make a video about matching diodes? Thanks! Alan, N8WQ

I have a partial ADC 20 conversion receiver section built but I'm not sure the 9 MHz IF filter is working properly--I don't have any 9 MHz crystals that have much Q, for one concern. I decided to built the ADC 40 receiver section so I could compare voltages and waveforms. I finished it today and it's working properly and sensitivity matches the original (stated in the article as 0.5 uV/-113 dBm). I matched up some 4 MHz crystals for the IF filter--the one I characterized had Q 140k. The VFO is set to around 7030 kHz (fix-tuned). The VFO buffer Q7 is interesting--it "sort of" squares up the sinewave from the VFO--that wasn't mentioned in the article. At 13.0 V supply (shown on the schematic as 13 V), no-signal receive current is 60.5 mA. (I don't have Q6,9,10 installed since I'm just interested in the receiver for now.) I didn't have a 12 uH choke (L3) so wound a T37-2 with 55 turns of #32. The 30 pF trim cap C14 wasn't enough to peak resonance so I added a fixed cap. I used a T50-7 (white) toroid for the VFO inductor L4. I'm using J310 jfets for both sets; 2N4401 bipolars from Mouser. 73, Steve AA7U

I had an idea to combine many different test jigs into a 80mm x100mm 2 layer PCB. So far I have the following test jigs on the board: 1. Inductor Q/Self resonant frequency test jig. This connects to your spectrum analyzer with tracking generator. It allows you to measure the center frequency and 3dB B/W in order to calculate inductor Q. It can alao give you an idea of the inductors self-resonant frequency. 2. Mixer diode forward voltage tester. Used your 13.8V power supply and a 2.7K ohm resistor to force 5mA across a diode to grade them for forward voltages. 3. Crystal oscillator for measuring the frequency of crystals so that they can be selected for crystal filters. The switch switches in and out a 39pF capacitor to measure frequency shift and allow calculation of Cm and Lm. A picture of the current lay out is attached. My question is, are there any other test jigs which might be useful in homebrew radio projects which could fit in the empty area at the bottom of the board? Steve WA6ZFT

I downloaded the parts list from Jim K8IQY's web site labeled "2n2_40+_new_piggy.pdf" and at the top of the list it says "revised for 11/23/2003 schematics". https://www.k8iqy.com/qrprigs/2n240+/KenyonCoxFiles-FlyingPigBuild/2n2_40+_new_piggy.pdf The only schematics I see are labeled "2N240+BA.SCH; 02012002". https://www.k8iqy.com/qrprigs/2n240+/2N240+Schematics.html Can someone point me to the newer schematics? Thanks... 73, Alan, N8WQ

I've watched this group for some months, and remember the hey-day of QRP-L and Manhattan construction when I was first getting into Amateur Radio. Recently re-licensed, I've been building back up my junk box and beginning to play a little. Chiefly I've started with old-fashioned proto-boards and the K3NG keyer. Digital is an easier way to begin building. IMO. I'm watching with great interest the revival/review of Manhattan building on this list. Thank you! I notice economics of building have changed somewhat. It's harder to stockpile a variety of parts without the variety-packs NorCal & others occasionally put together. SMT's can be a bargain, though, including variety-packs from ebay. Copper boards are not free, but custom PCB printing is dirt cheap, sometimes cheaper than the raw boards. Ugly/Manhattan are classic (and sometimes beautiful-- but not when I do it!) modes of building. "Limerick" as in the current-ish run of GQRP Sudden receivers (https://www.gqrp.com/sudden.htm) and Chuck's Muppet seem related as ways to evolve Manhattan. But I find really interesting pre-printed proto-boards designed to be flexible and easy to build on. For $5 for a handful (shipped!) they seem like no-lose propositions. The first I found was the W7RLF Protoboard: https://www.pcbway.com/project/shareproject/W7RLF_Proto_Board_Rev_2_2cd4857c.html This has great big pads for soldering to like Manhattan, spaced closely enough that perhaps SMD components could be used to connect them, too. But it seems really oriented to discrete components mounted in Limerick/Manhattan style. It has a full solid ground plane with the diamond shape pads connecting to it. I haven't yet wrapped my head around an easy way to use DIP IC's with this board (besides adding "sleds"), but the capacity to use header pins on the edges is a nice touch. This could be a nice board for an all-discrete build. Next I found the the Makerverse Protoboard: https://github.com/CoreElectronics/CE-Makerverse-SMT-Protoboard/tree/main This seems to be well suited for a mix of SMD's, IC's, and other through-hole components. Its "ground plane" is really a tight grid: I don't know how that will work for RF applications: whether it might be tight enough to act as a solid, or whether it might offer a lot of unwanted capacitance. Today I discovered the (6-8 year-old!) ElectronicEel protoboard: https://github.com/electroniceel/protoboard With the ground plane option, this seems to combine a solid ground plane with a little nicer (more ample for mature eyes!) spacing than the Makerverse board. Someday I need to learn KiCad or something and roll my own. A solid ground plane seems fundamental. I like the headers on the edges. I would love to add dedicated pads for BNC (and SMA), Barrel/power-pole DC connectors, and maybe PCB-mounted Pot's/switches. Maybe a power bus or two. Maybe some longer pads specifically for DIP IC's going down the middle like a traditional protoboard. A board like this seems like it could take away some of the fiddliest bits of home-brewing. With digital VFO's and $5 CPU's where one can program practically bare metal with high-level languages like Python, this seems like a great time to be a home-builder. Custom PCB's that are delivered for less than the cost of a couple gallons of gas is amazing. Custom PCB's that are flexible prototyping boards seem ideal for the experimenter. What proto boards have you found or do you like? Or, dare I dream, what KiCad maestro might feel inspired to roll the "ultimate" 2025 QRP home-brewers protoboard? 73 de Todd W2TEF

Here is a beginner project. You remember the VE3DNL WWV receiver standard. Found schematic online in a search for something else a few minutes ago. I know that some one (Nick?) did an improvement back in the day. My photo of the build attached with schematic. Thanks Glen, VE3DNL, for the work back in the days of old. For calibration of generators and frequency counters (the trusty FCC-1), I use a GPSDO (GPS disciplined oscillator) that has warmed up a few hours. Cost under $100 on ebay and other places. Aliexpress $67.74 USA vendor with 4.8+ rating and free shipping, but that is one that looked interesting. I'm sure some one here has splurged. chuck, aa7fo

I wanted to add these to topics already in progress but I can't find them using my phone, how do the Youngs do this? Here is a 24.MHz crystal opened up, sorry for the 007 view but it need some magnifying The crystal wafer is attached to the U shaped metal springy bits. The leads are attached to the inside of the U. The crystal was 24MHz fundamental and is commonly found on USB devices. I've seen the square flat bricks taken apart but don't have a link. Of course they were tested on my K7QO MUPPET G3UUR xtal tester from the transistor series that used to be on YouTube. I did manage to save a few of the episodes, but the project box ones (folded metal and pcb) were gone. The red color is from Krylon stained glass spray paint. I should have baked the board, bit chipped up after 7 years. Only strong rocks less than about 4 MHz or greater than 16MHz will oscillate. Have some fundamental 50MHz-ish rocks I need to make a circuit for. ICM used to sell a board that would work upto 60 Mhz with just some resistor changes. Enough ramblings Michael N9XYP

Michael et al, Attached are two photos of how I did it many moons ago. I used the 2.54mm spacing vector board with 3mm standoffs on the corners. As I worked with each crystal I placed in the next position. If you rotate the board 90 degrees counterclockwise, the #001 crystal will be in the upper left. Sequence the numbers going down and #21 is the top of the next column. Saved me from having to use coin envelopes, plastic bags and other additional items to keep things organized. Just make sure you don't drop these or have a cat push them off the workbench. Here, we have a no kids no pets policy in place for empty nesters......... Thanks for the laugh William, K6WHP. I am now in the parts scrounging/hoarding mode to rebuild the lab. The USPS elves are probably wondering what the heck is going on. I'm surprised at the number of parts you can find on Amazon. Got a 100 2N7000s coming cheap with free shipping. It's every man, woman and child for themselves. FYI chuck, aa7fo

Builders using Manhattan Construction (a.k.a Mad Hatters), 1. I use 2.54mm male and female headers for several purposes. See ebay and sort by price+shipping and search for the number you need. 40pin single row is what I get and cut to the number of pins needed. Using a PCB flush cutter, sacrifice on hole on the female strip by cutting dead center. The male strip has notch between pins. Image 2156.jpg shows using male headers for IC socket super glued to PCB. Note, plastic melts when heated, especially the nylon strip holding the male pins. 2. Image 3444.jpg shows header in center laying flat to plug in different band toroid for a regen receiver. Somewhere, outside the 4000+ images I current have in one directory, is an image of the module in place. This is a muppet board. For those interested in doing the SST-40 or SST-20, see Dave, AA7EE, web page. You can't do any better than that. But it is a great build and a great project. The problem is the LT1252 being obsolete and astronomical in price for the PTH part. I did an experiment with a TI TL592P, PTH part, 50MHz differential video amplifier with adjustable gain some time ago. 2659.jpg for the muppet board. Notes somewhere, but the part is $9 for 3 on ebay that I found. I think that a search for video op amps will do the trick to replace the part cheaply. Some one sent me, I think off line, a schematic for an SST with the IC replaced. I have had that schematic for a long time and built one. 1540.jpg is start and the rest is off on a DVD, if someone is interested. I also did a muppet board, the largest one I've ever done. Point: The ADC transceiver. I'm thinking of using the 2.54mm headers to build sections as modules and connect them neatly. Kindergarten training of keeping things inside the lines behaviour. This allows for testing of modules as I build them and possible improvements with tests and any updates you guys and girls find or develop. I'll also build the PCB version before letting the Gerbers loose. atx-40m.jpg board. I did buy two bottles of super glue at Home Depot. One loctite and one gorilla. The gorilla sets in 10 sec, the loctite a little longer. There is a use for both set times, I think. FYI chuck, aa7fo, the one who photographs work for no known reason, except to justify having a digital camera

In the spirit of "legacy" QRP rigs as mentioned by Chuck Adams AA7FO recently in his "Manhattan Circuit Construction Madness" post, I have decided to build a 2N2/40+ Transceiver designed and built by Jim Kortge K8IQY. I am going to build my 2N2/40+ using the manhattan style construction technique for my Spring Project. I am already having to scrounge for parts, lol. 2 MV1662 varactors that are used in the "Variable Xtal Filter" (D9, D10) 1 audio transformer, 1.2K ohm primary, 8 ohm secondary (T10) Does anyone have a source they can point me to for these parts? Keep the solder flowing! :) 73, Alan, N8WQ