I'm planning how to use the new Venus 838LPx-T timing receiver. Part of the reason for picking it ostensibly would be to parse the quantization error messages to make the phase discrimination more accurate.

But that requires more flash space, since the ATTiny841 is full at the moment. So I'm considering going back to the ATMega 328P. One of the luxuries that gives us is more pins. In fact, enough pins to hook up a 2x16 LCD for status instead of just two LEDs.

This immediately screws up the nice extruded aluminum case I've designed, unfortunately. That whole effort would need to start over. Additionally, adding the LCD adds about $20 to the cost of the unit even before accounting for the new case. I'm having enough trouble selling the units now because of the price tag. Adding features and raising the price might not be the best play.

I'm also considering whether I could come up with a phase discriminator upgrade kit for the previous generation GPSDOs. Such a kit would need to have a daughter board with the phase discrimination circuit and an ADC (because the Tiny4313 that was in use lacked one). The board would pick up Vcc, ground and one of the RF outputs from the board along with the SPI pins and an unused pin from the 4313 to use as a chip select for the ADC. So it means tacking 7 wires down to the board and upgrading the firmware. Not sure how many of the folks who bought an old one would want to do that.

EDIT: Well, the ATTiny841 has 8K of flash and the ATTiny4313 has 4K. So never mind the upgrade path.