This is a recreation of the Option 02 A5 Synt Board upgrade to suit the Tektronix AFG5101 Arbitrary Function Generator.

It will increase the accuracy of the function generator while in continuous mode (outputting a constant repeating waveform) from 0.5% to 50ppm.

It will also allow for 4.5 digits of resolution up from 3.5 digits.

There are a couple parts that are a little tricky to source:

• MC145145P1 or MC145145P2 (P2 type is a little better) - this will have to be sourced from the grey market.
• 74HCT4094 - these are no longer manufactured it seems, but can still be found new-old stock. They may be able to be replaced with 74HC4094 but the circuit will need to be tested to make sure they are compatible.

Link to youtube video on construction of this PCB:

https://youtu.be/v4a4lraYYQE