开云体育

Peeps,

HF Signals has rolled out the new (r4) version of the PCBs. Here are the
changes:

1. A new, low distortion audio amplifier made from discrete transistors.
This is one is optimized for head-phones and connecting to PCs for digital
modes. It does work with the small speakers as well. Builders with the
earlier versions can try this audio amplifier as an outboard amplifier.
2. The audio thump issue during T/R switching has been fixed.
3. At 28 Mhz, the output is about 4 watts. (this involves a single capacitor
change from the earlier PCB).
4. I have included some 'jump' points to add interesting stuff like CW
filters to the board. There are a large number of test points to help you
debug and understand the board.

All in all, the changes are 'backward compatible' . That is, you can hack
these changes to the previous boards to get in the new functionality. I have
updated the circuit diargrams on www.hfsignals.com. The earlier board's
circuit diagram has moved to


The bad news is that we had to bump up the price of the board by 20 dollars.
We fought long and hard to keep the price down. My personal ambition was to
keep the price inside (or at) $100. This is price rise has to do with three
things : The recent changes in the Indian import duty and sales tax; Our own
increasing costs to preorder the parts. Lastly, we also increased our payout
to those who wind the coils, assemble and test the boards. They were working
at the same rate for the last two years. It was about time.

The new boards cost $129 USD with shipping. $139 USB with DHL option.

The good news is that from now on, these boards will be available on order.
The waiting queue is gone.

On a personal note, I am happy with the new audio. It is so much sweeter and
cleaner on the headphones. Far less fatigue after hours of CW work. I am
also using the FT8 extensively, I have bagged almost twenty countries,
testing the new firmware.

- f