TL064 in PV 212 Deuce, VT Series, 1980

[N_Cook]

TI IC marked SN99661 and 70400604 and 604 on the schematic
A number of people (out there) enquiring about work-around of replacement
with 4016 or 4066 but no reports found of reported success.

The effects out one here, at first sight is doubled up of the 2 analogue
switches, but as c/o type only one used when it somes to it. 4066 sw about
4x Ron of a TL064 so that should be ok for all 4 paralleled for this PREA
output switching function. No problem finding space. I happen to have a
salvaged TL064 but will keep that for a rainy day. Anyone been here before
and can report success. Or a simple FET work around instead.

 

[N_Cook]

TI IC marked SN99661 and 70400604 and 604 on the schematic
A number of people (out there) enquiring about work-around of replacement
with 4016 or 4066 but no reports found of reported success.

The effects out one here, at first sight is doubled up of the 2 analogue
switches, but as c/o type only one used when it somes to it. 4066 sw about
4x Ron of a TL064 so that should be ok for all 4 paralleled for this PREA
output switching function. No problem finding space. I happen to have a
salvaged TL064 but will keep that for a rainy day. Anyone been here before
and can report success. Or a simple FET work around instead.

See the link below that has both a crossreference PDF for Peavey
parts, but also a PDF for the replacement of the TL604 part with a
small PC board.

Dan

Link: http://music-electronics-forum.com/t22020/


+++++

Thanks for that , I was looking for refs to TL604 and 4066

 

[N_Cook]

I have a Peavey Mace VT model of about the same age. If you want/need a
schematic, it may be best to get one directly from Peavey customer service,
as the one I was able to find online wasn't accurate in several areas, even
though it was an actual Peavey engineering schematic.

peavey mace deuce vt [2 MB]
http://www.schematicsunlimited.com/?z=peavey


I'm not certain that a schematic from Peavey would be more accurate, but it
could be.

In the downloaded schematic mentioned above, pin numbers of the footswitch
receptacle/jack (the jack has no connections at pin 3) and corresponding
circuit locations of those connections were different.. also there were a
couple of small capacitors present on the main board that weren't shown.

FWIW, a "fix" (contrary to an actual repair) solution I found regarding the
reverb section, was to jumper the TL604 location so the reverb section was
always on.. then just turn it down when not wanted.

--
Cheers,
WB
.............

TI IC marked SN99661 and 70400604 and 604 on the schematic
A number of people (out there) enquiring about work-around of replacement
with 4016 or 4066 but no reports found of reported success.

The effects out one here, at first sight is doubled up of the 2 analogue
switches, but as c/o type only one used when it somes to it. 4066 sw about
4x Ron of a TL064 so that should be ok for all 4 paralleled for this PREA
output switching function. No problem finding space. I happen to have a
salvaged TL064 but will keep that for a rainy day. Anyone been here before
and can report success. Or a simple FET work around instead.

The schema + overlays I downloaded in 2007 , source URL would be a workup to
back track to , are 8 jpg files named
Peavey_Deuce1a.jpg

....1b, .... 2 ... 3.... 4b
So far in full agreement with the Deuce of 1980 I have here. I say 1980 but
no confidence on that as IC datecode (probably as socketed) any more certain
dating of these

I'll give the plug-in SG211 mod with ribbon a go rather than circuit mod

 

[N_Cook]

Those jpgs may have been wrapped up as pv_deuce.zip

 

[N_Cook]

TI IC marked SN99661 and 70400604 and 604 on the schematic
A number of people (out there) enquiring about work-around of replacement
with 4016 or 4066 but no reports found of reported success.

The effects out one here, at first sight is doubled up of the 2 analogue
switches, but as c/o type only one used when it somes to it. 4066 sw about
4x Ron of a TL064 so that should be ok for all 4 paralleled for this PREA
output switching function. No problem finding space. I happen to have a
salvaged TL064 but will keep that for a rainy day. Anyone been here before
and can report success. Or a simple FET work around instead.

See the link below that has both a crossreference PDF for Peavey
parts, but also a PDF for the replacement of the TL604 part with a
small PC board.

Dan

Link: http://music-electronics-forum.com/t22020/


+++++


That adaptor would work as used in this amp , as single pole change over but
not generally for the 604 with 2 separate SPST alternately active as no
inverter in that package. One of the other unused 2 in the DG211 and a
resistor could perhaps be made to invert one of the control lines.

 

[N_Cook]

TI IC marked SN99661 and 70400604 and 604 on the schematic
A number of people (out there) enquiring about work-around of replacement
with 4016 or 4066 but no reports found of reported success.

The effects out one here, at first sight is doubled up of the 2 analogue
switches, but as c/o type only one used when it somes to it. 4066 sw about
4x Ron of a TL064 so that should be ok for all 4 paralleled for this PREA
output switching function. No problem finding space. I happen to have a
salvaged TL064 but will keep that for a rainy day. Anyone been here before
and can report success. Or a simple FET work around instead.

See the link below that has both a crossreference PDF for Peavey
parts, but also a PDF for the replacement of the TL604 part with a
small PC board.

Dan

Link: http://music-electronics-forum.com/t22020/


++++++

Back working again. A neat 1 x 3/4 inch matrix board mounted vertically,
enough space, with lowest .2 inches tied and glued around an 8 pin turned
pin socket to fit into the existing socket. Bridging wires dsoldered into
the turned pins. Sockets glued together as now a rockable assembly.

This is the node map
TL604 , DG211
pin1 , pin5
p2 , p8 + p16
p3 , p2
p4 , p7
p5 , p4
p6 , p6
p7 , p3
p8 , via 10K to p13

DG211 additional comps
p1 via 4K7 to p5
p5 low side of 5V zener high side to p12
p12 via SM 10K to p13

I've left the 2 unused 211 controls unterminated, as in pv cct, just in
case circuit critical but probably should be tied to DC

 

[N_Cook]

Good on you for doing a decent job. The "fix" solution I mentioned was
intended as a troubleshooting tip, as I stated "contrary to an actual
repair".

What surprises me is that there aren't dozens (or more) substitute ICs that
would work for this application of switching (even if not a pin-for-pin
exact replacement), since nearly every electronic product has eliminated the
use of real switches with keypads or other momentary button actuations which
latch/unlatch various features or functions (without using relays).

I won't be looking up switching ICs in databooks (as I might've done when I
was younger).. I'll rely on Peavey's solution, too.

With a SMD 211 I suppose it would be possible to make a direct plug-in pin
for pin space for space version. Then those unobtanium f dividers for old
synths etc

Today, hopefully replacing a cleaned out rotary "encoder" for a Yamaha amp
today and be able to reliably up/down select inputs again. But got me
thinking if you had to make one of these as a replacement, it would be quite
possible. Indented 10 or 12 position rotary but offs in the detent
posistions and off-radius pairs of contacts so outer contacts make
momentarilly before the inner pad between each dedent, clockwise and
opposite for acw

 

[N_Cook]

I have a few dozen 211 radily at hand and PV proven workaround and plenty of
headroom available