[Amps] Alphs 87a SWR Meter Diodes Shorting

[Rich Hallman - N7TR]

A few years ago I sent back my 87a to Alpha for a problem I was seeing
with the amp faulting on low or excessive gain - Fault 17.  They had
replaced the 1N5711 meter swr bridge diodes on the input.  Since then I
have had to replace these diodes 3 times myself...and again last night I
am seeing the same faults.  One indicator of this happening is the TUNE
indicator no longer works.
 
My question...has anyone else seen this issue?  Ideas on what's creating
the problem?  Is there an updated diode from the 1N5711 that I can use?
Also, the diodes that are shorting are the input SWR meter bridge....not
the output sensor 1N5711's.

Rich N7TR
ex KI3V, N3AMK, WB3JOV
www.n7tr.com
Telnet: dxc.n7tr.com N7TR DXCluster