24 September 2023

Crick Mint 20 a Homebrew Minimalist 20 Meter Transceiver Part I

 As I have said before in previous posts, I'm net to homebrewing. I have started working towards a homebrew sBITX but I feel that radio is much more advanced at what my skill level is. So to build up more experience, and to get a cheap pretty sweet transceiver to boot, I have decided to build a 4SQRP Cricket 20 designed by David Cripe NM0S and Virginia Smith NV5F


This transceiver was inspired by the infamous Pixie QRPp minimalist transceiver. (QRP in amateur radio terminology is generally considered to be a radio that is transmitting 10 watts of power for phone modes and 5 watts for CW and digital modes. QRPp is transmitting a power levels that are below 1 watt.) Even though there have been thousands of Pixie's made around the world, a probably logged dozens of contacts. It just did not have that special something to make it worthy enough for the prestigious 4SQRP name. So David NM0S and Virginia NV5F got together and came up with a design that is greatly improved over the humble and overrated Pixie. 

As you can see in the piciture above, the Cricket kits from 4SQRP doesn't have toroids to wind, This is a design feature by David NM0S thus eliminating the need for winding toroids. Another feature with the Cricket kits are  the on board straight key it is all powered by a 9 volt battery. Get a 49:1 UNUN and a 34 foot wire that is tuned to the frequency of your Crickets crystals (14.030 MHz and 14.060 MHz) and you can have a complete station that will easily fit in a pencil box. 

Please visit the 4SQRP Cricket 20 for more information about this wonderful little transceiver. A great read is the Introduction to the Cricket by David NM0S. 

My mission with the 20 Meter Cricket is to homebrew it and also have it fit in an Altoids tin if possible. There are some other changes that I would like to make if possible:
  • Remove the on board key. This will save a lot of space in the Altoids tin. Also I prefer to just add a key jack. I have to send CW with a keyboard and I need a jack to plug my keyer in. 
  • Increase the transmit power from 0.7 watts to 1 watt,
  • Possibly add a small speaker onboard
  • Get rid of the 9 volt battery. I would rather set it up to power it with a 12 volt battery so that it is standard across all of my radios. 
  • Add transmit and receive LED. Lights are cool. 
One feature that I would like to explore and see if it can be done with my Crick Mint 20. QRPGuys AFP-FSK Digital Transceiver III has an interesting way to make a small QRP radio multi-band. 

They have different modules that plug into the transceiver. Each module has all of the band specific components for each band. You could make a module for each HF band and to change bands you remove the current band module and plug in the band module that you want. This is something that I really would need help with but it would be pretty cool to have a multi-band Cricket.  Let me know what you think in the comments section below. 

That is about all for now. You can follow along this build by following this blog. Another place to follow along is the Crick Mint 20 Thread On the 4SQRP Group thread I will have discussions from other amateur radio operators about any problems or modifications that I make. 

Again if you want to follow this build or any future builds hit the subscribe button. Feel free to leave any comments in the comments section below. If you wish you may email me at Aaron@K5ATG.com

'72
Aaron K5ATG 

2 comments:

  1. Sounds like quite challenging project, Aaron. I built 3 different band Crickets and none of them receive anything, transmit ok. Antenna farm here is not the problem as all station works FB. There has been a lot of discussion about poor or no receive on the Crickets. Neat idea though. 72/73 de Karl, KO8S.

    ReplyDelete
  2. Thank you Karl for the heads up. I will keep that in mind.

    ReplyDelete

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