Hi Timothy
http://www.hfsignals.com/index.php/2017/11/23/bitx40-circuit-description/ - C103 , 3 pads between xtal and T4 on the PCB for the trimmer.
If those boards were an early batch (or you have modified) the diodes (2 with balance pot?) could well be mismatched. Replacing both should bring balance within the pot's ability, particularly if you measure them with an ohmmeter / DMM. Later versions had the ready-matched pair-in-one-package.
I've a dim recollection of BFO and VFO drive levels for the Bitx40 being discussed - they're adjustable in Raduino software for the uBitx and seem to make a difference.
You might find fragments of the diagram with specific modifications, but that one above is the 'master'.
Past messages in the Group give the info, as detailed on hfsignals site 'help'. Farhan has contributed here, researching his input would give the info 'from the horse's mouth' (as it were). development is ongoing in the Group, mainly for the uBitx but bits are applicable. Above all, READ. It's all in English (as here too), so our Spanish friends may encounter difficulties there - but if successful I'd encourage a translated site (a lot of other 'Latino' Hams would appreciate it!).
From hfsinals website:
If you need information specific to your shipping, billing and other commercial matters, you can drop us a mail to hfsignals¡¯ inbox at gmail. The mailbox is in the name of hfsignals followed by the regular gmail.com.
I feel sure an email there would gain Farhjan's attention, particularly being related to a group purchase. The boards as supplied will have a hand-written number on them; quoting those numbers will identify the batch and indicate appropriate steps - with luck replacements with latest versions, though stock may be low, the uBitx being the major production now. Who knows? I know Farhan and the whole crew are very helpful.
73 de ZL2DEX
