Back in August of 2017, one of these combo bass amps came through the Unbrokenstring Shop with cracked solder joints, which were probably a result of brittle lead-free (RoHS) solder on the circuit board. The owner of this Ampeg saw that post and called up the Unbrokenstring Crew to ask if this amp could be fixed as well. Here we go!
As was seen in the other repair, the metallurgy involved with the soldering process was to blame. In addition, in my opinion, this switch was not the exact part that matches the footprint on the circuit board. Note that the pins are bent inward to the center of the switch.
These pins are plated in gold. This is a good thing for the component, but gold, in solution with molten solder (yes, the metals mix) makes the resulting solder joint brittle. Here, some activated rosin flux is added to the gold plated pins to prepare them for a coat of tin-lead (non-RoHS) solder.
See the previous Ampeg 115 post for reassembly.
Thanks for reading all the way to the end!
CONTACT – David Latchaw EE