Re: Ref:Hilltopper 20 Manual, J5 and J6 headers

Charles W. Powell


J5 is for programming the ATmega328 and for I/O if you add the CAT control code, and J6 is for display, if you care to add it.  I can send you the info privately, off list if you want it.  There are several versions of the firmware around; I adapted it for my own use with some minor cosmetic changes.  (I’m not much of a coder - I just do a few doodles here and there.)

Great little radio.  I just built my second HT-20 and it puts out just shy of 7 watts!  With the audio mods, there is more than enough volume generally with the gain pot about half-way up.  I may change the sidetone resistor - again.  I still find the sidetone to be a bit loud for my taste.


Chas - NK8O

On Apr 30, 2019, at 8:35 PM, Eric Holzapfel <ewholz@...> wrote:

I have joined this group, very informative. I have just obtained a Hilltopper 20, and cannot find the section mentioned
in the manual about J5 and J6 - I have headers for this, but cannot find the info referenced in the manual
Online Support: Search for ‘’ on your browser and register to use their free service. Find ‘ and register to join. Once approved, find the HilltopperKit subgroup and register for it in turn. This is a group e-mail reflector and supports images and other file types. Please note that the J5 and J6 header strips are not provided in this kit- See the ‘Files’ section of the subgroup for more information.

Where is the files section? Is it possible to use the I2C pins (J5??) to show the freq??? Any info will help.


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