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The LARC Kit Builders Interest Group - updated 2018-02-17

Welcome to the web page for the group of LARC members who like to build electronic kits. This group is led by Dave McCarter VE3GSO who teaches our Advanced course, and who has taught electronics at Fanshawe for many years. If you're a kit builder, or would like to become one, come out and see what we're doing.

Kit Builder Meetings

Our get togethers are at the 427 Wing near the airport where our club station is, and are very informal. They run from 10:00 to 12:00 on Saturday mornings, and many of us attend the traditional “Hams & Eggs” breakfast before heading to the Wing. Participants are welcome to work on whatever kit they are interested in, and will find there are always people around to assist, help troubleshoot, make suggestions, test, and listen to your bragging when something actually works. We also have some test equipment available.

If you'd like to join this merry band of kit bashers, and get on our mailing list, contact Dave McCarter VE3GSO or Doug Elliott VA3DAE.

WARNING: Working on kits can result in solder burns, diminished eyesight, mental anguish when things don't work, and facial paralysis in a permanent grin when they do.

The inaugural meeting was on January 13, 2018, and more information on this and other meetings is available in the Meeting History section of this page.

Kit Builder Resources

One of the key roles of this web page is to share information that's useful to kit builders. Over time, we'll accumulate details here such as:

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Sources for general electronic parts

An online supplier listing for Canadians: http://www.island.net/~kdbrown/WhereToBuy-Canada.php

Top 10 USA Electronics Suppliers: https://www.instructables.com/community/10-Best-Electronics-Suppliers/

LocationStore TypeNameWebsitedeliveryknown OKComments
LondonBrick & MortarElectrical & Electronic Supply Inchttp://elelsu.com/you pick upyup501 Nightengale Ave near McCormacks
LondonBrick & MortarHardcore Electronic Supplyhttp://www.hardcore.supply/you pick upyup. new15 - 63 Clarke Road, London, ON N5W 5Y2
LondonHamDoug Elliott willing to share personal parts inventory with local hams
LondonHamDave McCarter willing to share personal parts inventory with local hams
LondonHamMitch Powell willing to share personal parts inventory with local hams
CanadaWebDigi-Keyhttps://www.digikey.ca/daysyuphuge. name comes from ham radio keyer
BC CanadawebActive Techhttps://www.active123.com/
USAwebJamecohttps://www.jameco.com
USAwebMouserhttps://ca.mouser.com/
CanadaBrick & MortarSAYALhttps://secure.sayal.com/zinc/index.asp yupTO, Markham, Barrie, Vaughan, Mississauga, Burlington, Cambridge
BC Canadawebrp electronicshttps://www.rpelectronics.com/
USAwebBG Microhttp://www.bgmicro.com/
USAwebSparkFunhttps://www.sparkfun.com/

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Sources for tools and test gear

( to be added - contributions welcome )

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Websites with tutorials, training modules, educational information

TopicInfo
SolderingIf you are new to soldering, there are resources on the web to help you get on the right track, soldering like a pro…
www.aaroncake.net/electronics/solder.htm (Don't worry about the steel wool stuff)
http://www.kpsec.freeuk.com/solder.htm

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Websites with reference information

( to be added - contributions welcome )

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Bragging from participants about current activity

Bragging is done on a separate web page, located at the brag board . To provide information (in any format that is convenient) about your projects, send an email to instructor@larc.ca

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Requested Assistance

You've probably had that sinking feeling when you go to put a chip into a socket, and inadvertently break off a pin, and there isn't a spare part in sight. Maybe you could add a nifty function to your project if you only had a particular part. Have you come to the point where you're ready to admit you have no idea how to do something that needs to be done to complete your project?

All of these situations are solvable by putting the word out to your fellow kit builders (or others who look at this web page) to find someone who can help you out. Several of us have inventories of electronic components that we are willing to share. Probably all of us have junk boxes with a random sampling of retired gear that still has usable components. There may even be some abandoned projects that can act as donors for those in need.

It doesn't hurt, or cost, to ask, so if you're looking for assistance, let me know. Send an email to instructor@larc.ca , and I'll get your request onto the following list.

PS: If what you need is described in the next section, “Volunteered Assistance,” just mention what you're looking for in a meeting, and someone is likely to be able to help you right away.

RequestorDateStatusDescription of the Request
Doug ElliottFeb 17openanyone take notes in Jan 27 meeting?

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Volunteered Assistance

One of the great things about groups like the kit bashers is that members can assist each other in various ways. When you're stuck on your project, having someone who can get you over the hurdle and on your way can make all the difference. Hams seem to have a natural tendency towards helping each other out, Elmering, and sharing. Following is a list of tools, techniques, skills, components, and experience that members have volunteered. How do you request some of this assistance? You show up at a meeting and ask. Please remember that this is all voluntary, and no one has a committment to work on your project for you or provide unlimited goods or services for free.

Volunteered assistance
Provision of small numbers of selected electronic components
Assistance with microprocessor work: Arduino, Raspberry Pi, PIC, etc
Troubleshooting a perplexing project problem
Use of specialized test gear like antenna analyser, etc
Use of Greenlee punches to make rectangular holes in enclosures
Use of a metal nibbler to make rectangular holes in enclosures

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Meeting History

Notes from our meetings at the Wing, in reverse chronological order, so the most recent meetings are described first.

Feb 17, 2018

-Tom's tapping a large coil for his tuner. Needed threaded studs to mate with threaded nuts embedded in the porcelain coil form.
Facca fasteners ( www.faccafasteners.com), or Laurie's ( www.lauriesfasteners.com) are good sources for things like threaded studs

-Barry's project with large pixie tubes with 11 leads. Trick is to trim leads in a spiral so you can insert them into the socket one at a time
-he's also working with a control/base board with surface mount (SMT) parts. We shared our condolences.

-Tip on removing multi pin SMT parts: use a piece of stainless 2 thou shim stock, which solder won't stick to. Heat the pins one at a time, and slip the shim stock between the part and the board, pushing it ahead for each pin.

-Doug passed around the mother board for his robot project. It now has all sockets and headers, and wiring is barely started.
-Dave examined soldering & said there are only a couple of bad joints (so far)
-key to good joints is keeping your iron clean and shiny tinned, heating both parts, and putting the solder on the parts, not the iron
-when you're wiping the iron tip on sponge or brass wool, twirl it for even cleaning action.
-teflon coated wire wrap wire recommended for jumper work, since the insulation doesn't melt when they're soldered

-Phil Harris is working on a code oscillator kit, for CW practice purposes

-Bill McHugh has offerred access to his bucket of knobs to the kit builders. Bill is generally regarded as an expert in electronic stuff

-Yaesu has announced a replacement for the QRP 817 that runs on batteries
-popular for summit work
-a pair of 817's is good for satellite work

-had a discussion on working satellites & related procedures & antennas
-satellite operations would make a good LARC presentation
-it would be great if we could work an ISS QSO into LARC 2020 - might have to rent some students

-Dave reports 3 London teachers want ham licenses to be able to use APRS for balloon tracking
-want classes/club to build uprocessor based boards as payload

-Harry has received his BitX transceiver, but not all of the related bits yet.

-Doug's note to self: add a section to this page titled “Bits and Pieces We're Looking For”
-if you need something, email instructor@larc.ca and I'll put your request where people can see it.
-includes components (chips, resistors, diodes, etc, project boxes, cables, connectors…)

-Dave would like us to actually do construction in these meetings, so bring your iron, your parts bag
and your instructions to the next meeting. Might want to bring first aid kit, too.

-to recondition old electrolytic capacitors, give them some current overnight. Put a 10 KOhm resistor in series with the cap and let some juice flow through it. This rebuilds the cap in mysterious ways that I don't understand. If you hear occasional clicking sounds, it means the cap is recharging up to the point where a fault in the dielectric insulation is allowing the current to arc over. The way you address this is by throwing the cap in the garbage.

-the session ended up with Dave doing a demo on how to use an oscilloscope over by the club station. Unfortunately, the scope and it's leads aren't fully functional, but we did see evidence of the FT-8 transmissions happening 5 feet away, and other stuff. We might do some more scope stuff next week.

Post Meeting Notes

-The wiki-whacker apologizes for the delay in updating this page, and promises to do better ion the future.
-we're now up-to-date, as far as I know.

-I've added a section for requests (“Requested Assistance”) to see if anyone can help with a part that is needed
-includes components (chips, resistors, diodes, etc, project boxes, cables, connectors…)
-could include access to test tools, design assistance, etc
-doesn't hurt to ask - worst thing that can happen is that on one responds
-forward your request to instructor@larc.ca and I'll get it listed

-I might add sub-pages for each member of the group in the “Bragging” section.
-it's a place for you to describe your current project.
-description can range from a single sentence to a full document with diagrams, photos, etc.
-don't worry about formatting the info. get it to me any way you can, and I'll include it.

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Feb 10, 2018

- Barry VE3DVV is working on a power supply project

- Terry showed off a few projects:

  • -Direct conversion LM386 NE602

Chinese built, can be a beacon. micorprocessor based, programmable

  • Rockmite II from QRPme: built in keyer, tone at 700 Hz, crystals
  • Pixie Forty-9er

-VHF 1 Watt transceiver: SV1AFN.COM

-QLG1 QRP-labs.com. Digital Xcvr. has GPS, can do WSPR with accurate clock. built in CW decoder

-QRPme.com is great for low cost parts

-Doug's garage door won't close if it's below freezing - safety beam falsely believed to be blocked
-eventually fixed it by replacing a 470 uF capacitor inside the infrared detector

-Should Doug replace capacitors with tantalums? No. GSO's story of shorting / healing tantalum faults, and
using a tattle tale - a JK flip flop - to trap a transient pulse.

-scope discussion - PC-based vs dedicated. no concensus that one way is better, but dedicated are getting cheaper

-basic tools for a kit builder include some sort of scope and a signal generator

-maybe a VTVM - vacuum tube volt meter. Hi impedance probes. good wish list item
that makes rapid changes visible

-Barry showed his ganged 4 part tunable capacitor from an AM/ FM radio

-GSO spun a story of a missed bargain on blowers at Forest City because they were monitoring his VHF bragging

-QEX (as in EXperimenters) magazine recommended for great in depth articles. Available only in dead tree edition

-There's a Brittish magazine line QEX as well, from RSGB (Radio Society of Great Brittain)

-there's a German TV board that takes HTMI in, and puts RF out

-UBNT.CA ( https://ubnt.ca/ ) is an outfit West of Owen Sound that is a wireless equipment distributor. They have gear suitable for Ham mesh networks, and well as lots of other stuff
-3.3 GHz as a clean frequency suitable for the spine of a mesh network
-mesh as an emergency support facility
-2.4 and 5.8 GHz can interface to spine, but are relatively busy and noisy
-mesh support for MS Tour?
-not expensive
-mobile ops doable
-for Trillium grant, need to sell application, not technology
. - need a strong plan and an early demo
. - ARES as driver of Trillium application
. - Terry has experience with location mapping

-Farhi as a resource we might be able to use?

-meeting regressed into story telling about CW practice

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Feb 3, 2018

-Terry has experience with BitX kits (or maybe he knows Kevin who has the experience?)

-Dave's DIY portable QRP tuner is beautifully documented in this PDF file (which might download stealthily. Check your downloads for QRPTuner.pdf).

-Tom's tuner
-frequency independence
-there's a well known design called the “St Louis Tuner”
-might not need all the capacitance

-Barry has received a CW Key kit from QRPguys

-discussions about:
-Beverage antennas
-Doug's robot (see bragging section of this web page for more details)
-switching power supplies
-Harry's Bit40 transceiver

-building kits to loan for new hams, vs. helping them find used rigs
-think the consensus was that used rigs are a better route for HF - kits are mostly QRP
-need to get new hams (like Dave Devries, who was present, and a graduate of last course)…
-an Elmer. Doug's action: assign Elmers to all students in course on the first day.
-offload course student monitoring to elmers, and post course follow up ?
-shack tours, to immerse them in reality
-involvement with club station - ready to go and generally surrounded by Elmers
-help getting used gear, and guidance at Hamfests.

-Dave needs an Elmer, and so does Ian, VA3WOT, who joined us for first time today

-should we have a LARC blog to keep students involved and up-to-date?
-challenge is always sustaining it over time with continuing fresh content
-our Facebook page does this sort of thing, but some of us avoid Facebook

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Jan 27, 2018 (Winter Field Day)

Doug was outside, freezing his butt off getting ready for Winter Field Day, and missed the Kit Builders meeting, if there was one. If you have any notes on what was discussed, please pass them along and I'll add them in here.

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Jan 20, 2018

-Al described his Neophyte receiver:
-40 M,, direct conversion, from Feb 88 QST article (some copies are blurry, but Dave has the original article)
-Dave McCarter has provided documentation of a new and improved version of this classic. You can find the PDF file here. (If nothing happens when you click, check your downloads directory for NeophyteReceiverV3.pdf - it may download stealthily and silently)

-FARCIRCUITS.com has zillions of printed circuit boards for ham projects available

-Hendriks / QRPkits.com also have lots of PCB's, many of commercial quality

-on a PCB, the ground trace should be big (wide) and close to everything

-when you're working on a kit, it helps to redraw the schematic, figuring out how each portion works as you draw it

-Dave claims it's easy to lay out a PCB, or maybe he said use “EASY PC” rather than “It's easy peasy”
-use toner transfer paper
-use photocopier (heated) to may copy from artwork
-be careful about flipping the image inadvertently
-clean and dry copper side of board, using acetone
-iron quickly to transfer
-dump in water bath
-do repairs with a sharpie pen
-immerse in etchant, about 15 minutes, then warm water

-request from the crowd for a list of recommended tools for basic and advanced kit building
-temperature controlled soldering iron. Al showed his Weller WES51
-a good tip has a large thermal mass to allow heat transfer without quick cooling
-different solders cool differently
-Eutectic solder, with a 63/37 tin/lead ratio is strongly recommended. From Wikipedia:

In specific proportions, some alloys can become eutectic — that is, their melting point is the same as their freezing point. Non-eutectic alloys have markedly different solidus and liquidustemperatures, and within that range they exist as a paste of solid particles in a melt of the lower-melting phase. In electrical work, if the joint is disturbed in the pasty state before it has solidified totally, a poor electrical connection may result; use of eutectic solder reduces this problem. The pasty state of a non-eutectic solder can be exploited in plumbing, as it allows molding of the solder during cooling, e.g. for ensuring watertight joint of pipes, resulting in a so-called “wiped joint”.

-Mike Cook notes that wooden paddles are better than plastic or metal for morse code keys, because they handle perspiration better

-for those of us who can't keep the names of morse code keys straight:
-a bug has horizontal action, and a single paddle
-a straight key has vertical action and a single paddle/handle
-an iambic key has horizontal action, and 2 paddles
-a side-swiper also has horizontal action, and 2 paddles

-Tom did a show and tell of the large open air capacitors he's using in the tuner he's building, and notes that you have to isolate the knob shaft.

-electronics-DIY.com has a good capacitance meter kit. They're Australian ?

-Hockey rink boards (as in being checked into the boards) are periodically thrown out and replaced. They're made of plastic that makes a great insulator

-if you need help with stepper motors, talk to Doug. I've used them on a couple of robots

-measuring the gaps in air capacitors
-micrometer
-feeler gauge
-they can handle about 750 volts per mil

-Tom's tuner design considerations:
-decide on power level it will be able to handle
-multiple antennas? Bypass?
-include a voltage balun (4:1) for ladder line, longwire?
-have an SWR meter, SWR + Power…

-an “ugly balun” consisting of a length of coiled coax imposes losses due to the length of the coax used

-a good book on Baluns was written by Robert Styvick

-a toroid labeled T-240-31 has:
- a 2.4 inch outside diameter
- a depth of “0”
- a permeability of 31. (31 and 61 are the common permeabilities)

-to make a choke balun, put coax around a toroid

-I have a scribbled diagram that shows coax entering a choke balun, and continuing to a 4:1 balun.

-Kits & Parts is a good source for toroids

-Smith Charts
-for visualizing RF circuits
-horizontal line is pure resistance
-uses logarithmic scale
-curves show reactance
-constant SWR curves - center = 1:1
-travel along a line to center, maybe multiple times.
-you'd probably be better to do internet research than try to interpret my cryptic notes

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Jan 13, 2018 - First meeting

11 people attended our inaugural meeting at the 427 Wing, and it was a relaxed get together with lots of story telling, advice, and project ideas. Thanks to Frank Birch VE3FBZ for these photos of the perpetrators.

conspirators

conspirators

We covered a lot of topics, interwoven with tall tales, confessions, and wish lists. A few of the discussion topics follow, and I'm hoping Dave can fill in more details and correct anything I've got wrong…

  • packaging your project in some sort of an enclosure can be the hardest part of building something from a kit. Dave showed a crafty way he had repurposed some fancy office conduit into a project case. Altoid Mints tins are also a traditional case for homebrewed gizmos
  • sometimes you can use electrical boxes from home improvement stores line Rona for enclosures
  • Making the right sized and shaped holes in your enclosure for connectors, switches, lights, etc can be a challenge. Some techniques were suggested:
    • drill a series of holes that outline the opening you want, then use small saws, files, teeth, etc to remove & smooth
    • Greenlee punches can be used to make square holes. Some members have these, and can help others
    • Metal nibblers can be used to expand a drilled medium sized initial hole into a rectangular hole. Again, there are members who have these and can assist others.
  • Speaking of assisting others (which is one of the major goals of this group), help has already been offered in a couple of areas. A “Volunteered assistance” section will appear soon to track these helpful offers, but there are members who:
    • can supply some electronic components from their own inventory
    • can help with microprocessor work, such as the Arduino, Raspberry Pi, PIC, etc.
  • one source of kits is the Alibaba website where many Chinese manufacturers sell kits. As always, you need to do a bit of homework to make sure any outfit you order from builds a quality product.
  • Lots of other potential kit sources were mentioned, and we'll accumulate a list in the Kit Builder Resources section of this web page. I heard Hendricks, Kits & Parts, QRPme, and BitX
  • Dave described the lightning detection system he has that detects lightning via a light level sensor on his roof. When it detects a sudden dramatic rise in light levels (i.e. lightning), an automated coax switch changes his rig from his antenna to a dummy load. Cool!
  • We do have some testing equipment available near the club station, and we have experienced people who can assist in those frustrating time when you can't figure out why the @%!*$ing thing won't work.
  • For some reason, I didn't take notes when we did the round table on the kit projects people were thinking of working on. Going from my feeble memory, these are some of the ideas:
    • Keys and Keyers for the CW course that has just started up
    • battery chargers of various types
    • Baluns for antenna feedlines
    • Remote station operation
    • attenuators
    • various kits that were started in the past, but never quite completed
    • weather-proof radios

Post Meeting Notes

  • Thanks to AL VE3GAM for providing 4 more kit websites
  • thanks to Mitch Powell for volunteering to share his own parts inventory, and for pointers on soldering advice

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lig-kits.txt · Last modified: 2018/02/19 01:46 by 99.249.24.176