Ashton GA80 guitar amp (Australia)

N

N_Cook

Guest
RoHS date of introduction for Australia ?
Anyway 1/4 inch i/p socket too weak even for domestic use , breaking up in a
few years ( within RoHS regime), no obvious datecodes except main electros
seem to be 2000, otherwise maybe 2004 or 2005 IC dates. No-name flimsey junk
, the type with 2 insulated change over contacts. On trying to work out the
functions, apart from the tip contact/grounding setup there is a line to one
of the isolated switches that grounds at plug inserted and o/c when removed
, it goes DC connected to the base of a pnp transitor - function ?
 
N_Cook <diverse@tcp.co.uk> wrote in message
news:hder6j$jg8$1@news.eternal-september.org...
RoHS date of introduction for Australia ?
Anyway 1/4 inch i/p socket too weak even for domestic use , breaking up in
a
few years ( within RoHS regime), no obvious datecodes except main electros
seem to be 2000, otherwise maybe 2004 or 2005 IC dates. No-name flimsey
junk
, the type with 2 insulated change over contacts. On trying to work out
the
functions, apart from the tip contact/grounding setup there is a line to
one
of the isolated switches that grounds at plug inserted and o/c when
removed
, it goes DC connected to the base of a pnp transitor - function ?
Click to expand...
If it kills the gain for bang-less plug insertion then it would only work
for insertion , not removal, as that switch makes before tip makes/breaks
ground
 
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:hdghi1$lb7$2@news.eternal-september.org...
N_Cook <diverse@tcp.co.uk> wrote in message
news:hder6j$jg8$1@news.eternal-september.org...
RoHS date of introduction for Australia ?
Anyway 1/4 inch i/p socket too weak even for domestic use , breaking up
in
a
few years ( within RoHS regime), no obvious datecodes except main
electros
seem to be 2000, otherwise maybe 2004 or 2005 IC dates. No-name flimsey
junk
, the type with 2 insulated change over contacts. On trying to work out
the
functions, apart from the tip contact/grounding setup there is a line to
one
of the isolated switches that grounds at plug inserted and o/c when
removed
, it goes DC connected to the base of a pnp transitor - function ?



If it kills the gain for bang-less plug insertion then it would only work
for insertion , not removal, as that switch makes before tip makes/breaks
ground
Click to expand...

Maybe it mutes the reverb?



Gareth.
 
Gareth Magennis <sound.service@btconnect.com> wrote in message
news:8gQKm.112991$F%2.69151@newsfe19.ams2...
"N_Cook" <diverse@tcp.co.uk> wrote in message
news:hdghi1$lb7$2@news.eternal-september.org...
N_Cook <diverse@tcp.co.uk> wrote in message
news:hder6j$jg8$1@news.eternal-september.org...
RoHS date of introduction for Australia ?
Anyway 1/4 inch i/p socket too weak even for domestic use , breaking up
in
a
few years ( within RoHS regime), no obvious datecodes except main
electros
seem to be 2000, otherwise maybe 2004 or 2005 IC dates. No-name flimsey
junk
, the type with 2 insulated change over contacts. On trying to work out
the
functions, apart from the tip contact/grounding setup there is a line
to
one
of the isolated switches that grounds at plug inserted and o/c when
removed
, it goes DC connected to the base of a pnp transitor - function ?



If it kills the gain for bang-less plug insertion then it would only
work
for insertion , not removal, as that switch makes before tip
makes/breaks
ground




Maybe it mutes the reverb?



Gareth.
Click to expand...
Luckily the owner wanted a reliable input socket and was unconcerned about
the loss of the plug-in de-thump cct. To replace the domestic headphone
socket (has isolated switching) would have been a work up as 0 or 15V on
that control line so could not use an effects pedal type ring switch action.
And the ring switch for a normal stereo 1/4 inch jack is the wrong action
for here anyway, requiring an inverter somewhere or one of those awkward and
rare offset 1/4 inch switch actions. cct proper, holds off full gain for 0.5
seconds or so after plug insertion, all the while removed 30dB or more gain
drop via 15/-15V control into the first amp. Although no obvious PbF solder
problems the original input socket had thin+wide blade pins going into holes
of that wide diameter and loads of filler solder, asking for problems with
ordinary solder let alone new-fangled


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
More as a reminder to myself, for the next time this problem appears. A work
around without having to cut into the existing cct to put in an inverter.
Use a small SPDT relay (+emf diode) with power adapted from whatever
convenient rail.
Permanent ground on the flexing ring contact in a 1/4 inch TRS socket and
the fixed ring- contact to the low side of the relay.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
N_Cook <diverse@tcp.co.uk> wrote in message
news:hdj5bg$du7$1@news.eternal-september.org...
More as a reminder to myself, for the next time this problem appears. A
work
around without having to cut into the existing cct to put in an inverter.
Use a small SPDT relay (+emf diode) with power adapted from whatever
convenient rail.
Permanent ground on the flexing ring contact in a 1/4 inch TRS socket and
the fixed ring- contact to the low side of the relay.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
Click to expand...
The added delay, due to relay action, only adding to the desired effect of
delaying the removal of the gain suppression until after tip contact is made
( unless someone is very slow at plug-in)

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
On Nov 11, 9:10 am, "N_Cook" <dive...@tcp.co.uk> wrote:
RoHS date of introduction for Australia ?
....snip...
Click to expand...
the answer I got was,
"Not on the radar."
 
Robert Macy <macy@california.com> wrote in message
news:b8a9f51b-aca5-484a-8981-42f42654ef87@12g2000pri.googlegroups.com...
On Nov 11, 9:10 am, "N_Cook" <dive...@tcp.co.uk> wrote:
RoHS date of introduction for Australia ?
....snip...
Click to expand...
the answer I got was,
"Not on the radar."


RoHS printed on pcb overlay, and definitely grotty PbF-looking solder (but
not any actual observable or twizzleable bad joints). No RoHS stickers on
the outside, so presumably standard asian product internally, badged as Oz
externally
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top