During the weekly F-troop there are mentions of software, websites and solutions that are worth taking note of. This website attempts to document them.

20180616 - Terminating a BNC connector

posted Jun 15, 2018, 6:55 PM by Onno Benschop   [ updated Jun 15, 2018, 7:01 PM ]

Charles NK8O has written this description on how to terminate a BNC connector.

First, I use 90 degree angled BNC connectors because there is no center pin with which to deal. It removes a level of complexity from the process.

Since I am making mostly jumpers for the shack, I use RG8X cable. It is flexible enough to be manageable and small enough not to be cumbersome.

BNC 90 degree crimp connector for RG8X/LMR 240. Don’t skimp. Use good quality connectors like Amphenol. That’s what I use.
Inside the connector is a notch for the center conductor.
ALWAYS remember to put your heatshrink (if desired) and the ferrule on the cable FIRST. (Don’t ask how I know this!)
Measure out the length so you have an idea where to strip. You can mark this or eyeball it, if you clever.
Use decent quality tools to do your stripping and crimping. Those crimpers are available at hamfests or rallies, and also from Amazon or your local Amateur Radio candy store.
Do the “deep” cut from the tip first. Note there is an indication on the tool to show the direction to turn. Do NOT make an excessive number of turns or you will damage the center conductor. This tool was purchased with a cable TV crimping set for RG6 - same size as RG8X.
This length is good. If you are very fussy, you can allow the white inner insulation to go all the way to the solder point, but it’s not necessary.
Then strip the outer sheath. A good tool requires ONE turn. Otherwise you cut and fragment the shield weave.
Flare the braid and insert the wire in the connector. The inner conductor should just rest in the channel.
Bring the ferule up into place. It should fit semi-snugly on the braid. Push everything up into the connector until there is no inward play, and make sure the ferrule is snug against the body of the connector.
Engage the crimping tool with everything in place, and crimp. The top of the tool (with lettering, etc., goes toward the body of the connector.
A good crimp will have a uniform hexagonal shape. The bottom flares, uncrimped. Some folks like to try to crimp all the way down with a second pass. I think it usually makes them look sloppy.
Use a HOT soldering iron or it will take you all day to heat the wire and the channel brass. Tinning is not necessary if you heat everything properly, except to tin tip of the iron to facilitate heat transfer. Temp shown is Farenheit, which about 480C. The hot iron allows you to work quickly.
Hold the work in place with a “helping hands” to avoid burning yourself. I like to wrap something around the ferrule to prevent scratches, even though it will be covered with heatshrink.
Solder should show a good “flow". The trick is not to allow any to go down the outside of the channel support or drip inside the connector. This is a good time to check for shorts with a multimeter.
This is Harbor Freight heat gun. Harbor Freight is a tool and utility chain in the US. A heavy duty hair dryer *might* do the job, but many do not get hot enough. Excuse my green scrubs - it’s my work uniform!
Heatshrink is cured in place with the heatgun, and the cap is installed over the connection. Tighten the cap gently and the process is complete.
The final product with a PL-259 at the other end. The method of crimping is identical, although the measurements are a bit different. With the PL-259, be careful to keep solder off the outside of the center pin. This is a 1 metre long cable.

#tutorial #nk8o #soldering #crimping #bnc

20180616 - Comments on the LCD

posted Jun 15, 2018, 5:55 PM by Onno Benschop

The WIA is preparing a submission to the ACMA for an update to the LCD. Have a read and please comment.

20180616 - ARRL Field Day

posted Jun 15, 2018, 5:49 PM by Onno Benschop

Charles NK8O reminds us that if you want to work DX with the USA, next week is a great time to do that:
#portable #contesting #nk8o #dx

20180616 - SDR receiver

posted Jun 15, 2018, 5:35 PM by Onno Benschop

Glynn VK6PAW reminds us that there is a network of software defined radios which allow you to potentially hear your own HF signal:

20180616 - Soldering

posted Jun 15, 2018, 5:10 PM by Onno Benschop


20180616 - BG7TBL noise source

posted Jun 15, 2018, 5:06 PM by Onno Benschop

Denis is making noise with this:

20180609 - Plastic Fantastic Magnetic Loop

posted Jun 8, 2018, 5:44 PM by Onno Benschop   [ updated Jun 8, 2018, 5:51 PM ]

Denis VK6AKR points us at a magnetic loop antenna built from gas line pipe which are lined with a conducting material. Project description by Jim VK5JST:
Some other projects that Jim has documented can be found here:
#magneticloop #vk6akr #vk5jst

20180526 - Kits to build ...

posted May 25, 2018, 5:46 PM by Onno Benschop   [ updated May 26, 2018, 9:50 PM by News Team ]

Charles NK8O has been building some kits, including the QRP Labs QCX 5Watt CW transceiver and the Four State QRP Group Hilltopper.
Inside the Hilltopper 20.  It uses conventional architecture but with some modernization. Frequency generation is from an Si5351 chip, using a stock Adafruit board, and control is via an ATmega328 chip using Arduino code (fully hackable).  It is a superheterodyne configuration and uses a 4 pole crystal filter.  The design is by Dave Benson, K1SWL, of Small Wonder Labs fame. He “retired” but you can’t keep a good man from designing great radios.  The construction manual is among the best and most logical i have seen. All surface mount parts are pre-soldered.

There is no display.  Frequency is via annunciator, played when the push button is touched.  Gain is all controlled at the front end, using RF gain.  There is a built-in keyer and auto sensing for a straight key.   The latest firmware offers Curtis mode A & B keying.  The radio chassis is a very clever use of PCB board.

Old school setup.  Paper and pen for logging and Hungarian straight key (at 18-20 WPM).  The “other” radio is an old R4030, the TenTec rendition of the HB1B.  T1 tuner from Elecraft also was a recent build.

20180512 - Programming the Ailunce HD-1

posted May 11, 2018, 6:44 PM by Onno Benschop   [ updated May 11, 2018, 6:46 PM ]

Carsten VK6PCB has shared with us a guide to programming the Ailunce HD-1 DMR radio.

20180421 - Air Variable Capacitor

posted May 3, 2018, 11:51 PM by Onno Benschop


Roger VK6FRAN has been building rotors and stators as one stack to construct an air variable capacitor. Denis VK6AKR said:

Roger milled all rotors and stators as one stack over about 55 minutes.   The time could be reduced, we believe, by being more aggressive with our feed parameters and choice of lubricant but such is the nature of experimentation!

His next intention is to add a fine tuning capability.   Now to locate a nice loop design that can tune with around 20 to 25 pF.


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