SOME ADVICE YOU MAY FIND
I don't do any repairs, re-engineering, or custom building of new
audio systems since I retired in 2012.
For repairs to any audio or other electrical items, I only know one other man
who may be helpful. I will give you his phone number if I think he can fix your
may need to be able to do very basic diagnosis of your problems........
B. Turntables &
C. Cassettes & tape.
E. AM Radio.
Some old amps.
H. A World fulla junk.
To avoid unnecessary repair costs if one channel of your audio
system does not work....
(1) Make sure both speaker leads
are correctly connected at the amp and at the speakers.
If you have 2 speakers, there
are 8 possible connections which could be faulty.
(2) Inspect speaker leads for
any breaks in copper wires within cables, badly done joints
where wires have been loosely
twisted up, but not soldered, and missing insulation.
(3) Make sure you have connected
wires to speaker and amplifier terminals correctly
with red or marked speaker wires
to red terminals, and black or unmarked wires
to black terminals.
(4) Look for where any bare
copper wire or strands of wire could touch each other.
If any speaker wire makes a
direct stray connection with any other wire or part of a
metal amp chassis the amplifier
may become faulty.
(5) Most amplifiers do not have
fuses or adequate protection circuits to prevent failure
with faulty speaker wiring.
SPEAKERS BOTH OK?
(6) After examining
cabling and connections and if only one channel works, TURN OFF
the amp and REMOVE the speaker
cabling to the silent speaker at the rear of the amp.
TURN ON the amp and the
remaining speaker should continue to work.
(7) TURN OFF the amp, and
disconnect the working speaker with the other silent speaker
and using the same speaker cable
from the same working amp channel.
TURN ON the amp, and if the
speaker is silent, then probably the speaker has a serious
If you hear only low level high
frequency sound, the speaker is faulty. If there is distortion
or buzzing above a low level,
the speaker is faulty.
If the speaker works fine like
the other one, both speakers are OK, and perhaps the
cabling to the silent speaker is
faulty. Re-examine the cable carefully.
Were you using the correct red
& black terminals for each Left and Right speaker?
IS THE AMP
(7) TURN OFF the amp
and move the speaker cabling of the working speaker from
its red&black amplifier
terminals to the 2 red&black vacant terminals of the other
(8) TURN ON the amp. If the same
working speaker gives good sound on the
other channel, then both amp
channels are working, and the suspected fault in the
amp does not exist.
And therefore one speaker or its
cable or connections are faulty.
(9) If a good speaker with a
good cable still does not work on one channel,
re-check the cable connections,
and if the known good speaker still does not work,
then the amp MIGHT BE faulty.
(10) Try selecting other stereo
signal sources, say FM tuner instead of CD player.
If both amp channels then work,
the fault may be within the signal source unit,
or within the amp input
terminals, or within the input cabling between CD player and
to amplifier. If "mono" is
selected and sound comes from both amp channels then both power
amp channels work, but the
preamp part of the whole amp set up may have a fault.
At this point, most owners are
unable to diagnose further. An owner can only
diagnose whether the speakers
and cables are faulty OR the fault is somewhere in the
amp or chain of connected
components all with interconnecting signal cabling.
When someone has a turntable
followed by phono amp followed by line stage pre-amp
followed by power amp, there are
12 plug in RCA connections, and possibly the same number
of non soldered wire joints at
ends of RCA cables. Old RCA cables can become intermittently
connected if they have broken
inner wires, crimped joints which have become loose, or broken
solder joints. A total system
check may need to be done and I may be of assistance.
B. TURNTABLE and
Most TTs have rubber
drive belts which degrade over time. There are cheap generic
replacements with a range of
belt section profiles, square, circular, rectangular and a range
belt lengths available
However, most people cannot
measure the wanted belt length or estimate what profile
if the original belt is missing,
and the expert in the field must be employed.
If the TT turns on and platter
turns OK, but the record won't play properly, there could be a
range of possible problems. The
"stylus" at end of arm is the "needle" which is supposed
to rest lightly in record
grooves, usually with force between 0.5 grams and 4 grams.
Does the arm swing wild across
the record after the stylus is lowered onto the record?
Is there a stylus to be seen? It
is a tiny delicate rod about 1.5mm dia protruding about
10mm horizontally from the
"cartridge" at the end of the arm. It may have been broken
off the TT any time in the last
40 years since the TT was last used, or, it is there, but bent
badly, or the tiny diamond at
the end is missing, and sound is dreadful. There is often a
tiny rubber ring which locates
the stylus in its little holder, it is prone to warping and
with age. There may be a
replacement cartridge available for the old cartridge you have
Email your TT brand and
cartridge brand and all identification numbers to
Ph +61 (02) 4328 1108
Mob 04 888 0801
Fax +61 (02) 4329 5383
104 Carrington St, Narara, NSW
Nerida is excellent to deal
with via mail order and the minimum stylus cost is
about $50, with a maximum far
She has replacement cartridges
with a new stylus which may be used to replace the
cartridge you have and for which
there is no longer any available stylus. The Nagoaka
Japanese made cartridges she
sells are probably equal or better than many made long
However, the fitting of
replacement cartridges is often beyond an owner's capability
there are delicate nuts and
bolts to cope with, and possible problems with connection of 4
wires to 4 contact points. The
existing wires and contacts at the end of the arm can become
brittle with age and thus give
very poor connections which will result in noise and
Not all TTs have easily
replaceable cartridges, and many such TTs are simply not worth
restore, as they will never be
better than the awful low cost rubbishy TT one might buy
from Dick Smith or Jaycar,
recently made crudely somewhere in Asia. There are a range
of better TTs available from
local hi-fi stores, but you pay more. Many of the best TTs were
made 35 years ago, before the CD
The force needed to hold the
stylus in the groove as the record rotates is usually between
0.5 grams and 5 grams, and best
sound is only possible if the "down force" is adjusted
to the correct value. Good TTs
have an arm with an adjustable balance weight and
down force setting dial to get
the down force correct for any chosen cartridge.
If there is no means of down
force adjustment, you have an awful TT.
Sometimes the arm does not
respond correctly when start / stop levers or buttons
are pressed, or arm does not
lift or lower to record with provided lever. There may
be faults with mechanical items
"under the chassis." The kind of faults are too numerous
for me to describe here and if
the arm won't "go through its motions" properly the unit will
need a repair or service. Costs
of repairs and stylus
- cartridge replacements usually
between $50 and $200.
Some TTs have circuit boards
with complex electronics to control the platter motor and its
Many were made in 1970s and replacement electronic ICs used may
be impossible to find.
Although some were magnificent performers and solidly made, they
may not be repairable.
C. CASSETTE / TAPE
have become dinosaurs, except for hundreds of people with
cassettes, some going back to
People with collections of
cassette tapes and/or reel to reel 1/4 inch tapes may wish
to preserve them by transferring
to a CD. This may be
too difficult for them to achieve with
a PC, or their tape player is not able to be fixed. They may seek help
Artsound street address:-
Manuka Arts Centre, Cnr. NSW
Crescent and Manuka Circle,
( right behind Manuka Oval, next
to cricket nets ) Manuka.
Telephone Office : +61 ( 0 ) 2
A common problem with old
loudspeakers is the disintegration of foam surrounds around
the outside of bass or midrange speaker cones which are
unusually the large "round
at the front panel of a speaker when the fabric cover is
removed. Between 1994
I repaired many speakers with degraded surrounds but the number
much reduced before
2010. Imported new speakers have become so cheap, although often
not any better than old
speakers which have never been abused, and are able to be
I often used very suitable butyl
rubber speaker surrounds which were sold by Jaycar
in 3 diameters, 300mm, 250mm and 200mm. I don't know if Jaycar
still sell them or where
else you could get them. A latex based glue is needed for fixing
them and care must be taken
with complete removal of the old surround and its glue, and the
the alignment of cone must be
perfect, and fit of the surround also perfect, and unless you
know what you are doing after
lots of practice, replacing speaker surrounds is extremely
difficult to get right. Don't settle for
foam surrounds because they may again fail sooner than the
Pairs of stereo speaker
surrounds always degrade together and if only one appears
to have disintegrated, the other
will be close to disintegrating. Many generic and cheap
speakers purchased over 20 years ago may not be worth repairing because the enclosure
box has developed unsightly faults usually caused by swelling of particle board used to
make the boxes, or plastic sheet covering is peeling off. However, some of the better brands
high quality hi-fi
speakers from the past may be worth repairing.
I have occasionally entirely
removed all damaged drive units and replaced them all with a
well selected set of 6 Peerless
made-in-Denmark drive units, bass, midrange and treble
This sometimes involved
replacing the front panel of the speaker and cloth fabric cover.
The crossover filters were
re-designed and re-built. The speakers became virtually
brand new. I used to charge up to around $1,000. The result was
ALWAYS better than anyone
could buy an equivalent pair of new speakers at Duratone Hi-Fi
or Miranda Hi-Fi.
I sometimes repaired tubed AM radios or radiograms from
1950s or 1960s.
Some had small Bakelite cases while others had elaborate veneered timber in large
standing cabinets. Many such old radios made after the 1930s
have belonged to a well
remembered old relative, and offer a window to a past.
All such radios need a huge number of hours of work to properly
restore. I sometimes spent
several weeks totally re-building and rewiring the whole item.
This was always needed tp
prevent future failures during the next 50 years, and to improve the sound quality to meet
people's present expectations.
I could find new replacements out of old stocks of never used
tubes for some of the old
vacuum tubes made between 1935 and 1950, but not always.
I often had to completely redesign the circuit to accept tube
types made between 1950
and 1965 to replace an unobtainable older tubes. The customer
ended up with a far better
tube radio that was ever provided by the original manufacturer.
The present use of many modern household appliances and
compact fluorescent lights
creates serious noise interference with AM band reception with
old radios which usually
had an antenna which was 3 metre long piece of wire taken
from the radio to some
convenient point on a wall or window curtain rail.
The only effective solution
to the noise problem is to replace some parts of the input
of the radio with a custom made "ferrite rod antenna".
rod is a 10mm dia rod about 200mm long and made from iron based
bonded together for required magnetic properties at AM broadcast
between 500kHz and 1,750kHz. Such a rod is wound with
approximately 40 turns of well
insulated wire, such as 1 strand of plastic insulated wire from
a Cat 5 cable, or old telephone
hook up wire, with a solid single 0.5mm dia conductor. The exact
number of turns on the coil is
extremely important so that the inductance is just right to be
able to form a resonant circuit
between 550kHz and 1,700kHz with the existing tuning capacitor.
The inductance is varied
by having the coil on a sliding cardboard former and mounted
about 1/3 the way along the rod.
The tuning of stations by the rod & coil and must co-incide
with the tuning of the existing
oscillator coil. This is known as "tracking" and it is the work
of an expert to fully understand
and implement ferrite rod installation. The length of any leads
from input tube and coil are
kept as short as possible. The result is clear reception of
strong local stations.
There are two parts of any electromagnetic radio wave, the
electrostatic portion and
magnetic portion. The majority of noise is conveyed to the set
by means of electrostatic nature.
It appears the fluorescent lamps modulate the wanted radio
stations electrostatic waves
so you get a loud hum when tuning to a station. But the ferrite
rod is sensitive to the
magnetic portion of what is transmitted, and not to the noise
Before 2000, there were few things that caused electrostatic
interference. Now there
is much noise. So I began to install a ferrite rod antennas to
all AM radios so people
then enjoyed their AM.
Of course if people didn't mind
the poor sound and noise in a radio which is simply
repaired to original condition, then the cost of a repair might
be as low can be as
low as $75, not including any repairs to the unsightly condition
of timber, Bakelite or
For old large floor standing
radios or radio-grams which have pleasing woodwork, there
may be very much more work
needed to give better sound free of noise and to restore
the woodwork finish. I have often installed an extra switch and
rear panel RCA terminals
to allow use of other sound sources such as a CD player, i-pod, or other source.
old radios have only one speaker and one internal audio amp so
the sound can only
be mono, not stereo, but they can still offer very good
listening when the stereo sound
source is combined for mono sound. I rely on a mono sound system
in my kitchen which
has a tubed AM radio of my unique design, plus a Pioneer FM
tuner. The single EL34
in triode mode with 1953 Rola Deluxe 12" speaker plus 1974
Foster dome tweeter does
very well with any music recorded by the Australian Brandenburg
I suggest those wishing to fully re-build an old radio in a large cabinet should go
page on Radio-re-engineering.
or AM/FM tuners are mostly solid state and don't suffer from
noise or poor
reliability, and remain OK after 40 years so far. Usually the AM
from most generic AM-FM
tuners is not good, with audio bandwidth limited to 30Hz -
1.5kHz. The Ferrite rod fitted
may/may not be effective against hum from lights and other
Many people complained about noise and lack of signal. Its
usually because of a
poor FM antenna, or the antenna is wrongly connected.
Most FM antennas are nominated as either 75 ohms or 300 ohms.
You don't need to
know what an ohm is but you do need to know there is a
difference and usually most AM/FM
radios, receivers, or tuners have terminals on the rear panel
and labeled 300 ohms or 75 ohms,
and YOU have to make sure the antenna you bought from Jaycar or
Dick Smith Electronics or
wescomponents.com.au is connected to the correct terminals. Many
75 ohm connections
are similar to an RCA socket, ie, a round thingy about 7mm dia
with a central round hollow
thing that connects to something plugged in. A 75 ohm antenna
should have a plug to suit the
standard socket you may have. But many old tuners have screw
terminals, which means the
owner has to be technical with a screw driver, and this is quite
Most FM antennas are simple flexible wires of a correct length
which may be pulled straight and taped to a nearby window frame
trim, either vertically or
horizontally, but so that the tuner works on all FM stations
with enough signal to achieve
noise free operation.
AM function of many old tuners or receivers is usually
determined by an existing internal or
attached "rod antenna" maybe 150mm long which swivels 90 degrees
from rear of unit to allow
best reception from most stations in one position. Some have
small "loop" antennas which clip
on the rear of the tuners/receiver. These often get broken off,
lost, and unless you get the
exact equivalent AM antenna, AM reception will be very poor, or
state tuners or receivers cannot be modified or be
re-wired. But most of the circuit chips
are still available for anything made since 1975.
FM reception is often the most reliable sound source of all
possible sound sources such as CD,
vinyl, i-pod, etc, but occasionally I have had to try to fix a tuner
which resists all attempts to make
it work properly, and they can be difficult to diagnose because of the
circuit complexity, and
perhaps because of just one little thing which malfunctions
intermittently, but that little thing
is very hard to pin-point.
I have not had anyone bringing
me a digital radio for repair. The sound quality is supposed
to be good, and better than old
fashioned FM, where many pop music stations have
applied high "compression" to
make the sound louder than the next station along the band.
Digital circuitry in a digital
radio is so very complex and miniaturized that one can only
modules or the whole radio if
there is a fault.
SOME OLD AMPLIFIERS.
Some amps arrived here in extremely poor condition. Sometimes
they were potentially "collectable"
items which may have had some value if restored, eg, a pair of
Quad-II amps, or Leak 2020,
with missing or smashed tubes, rusty metalwork after storage in
damp, and have
a dud OPT or PT and have never ever been serviced since 1955.
Descriptions of my work
on such items are explained within other pages at this website.
A pair of
Quads can take
weeks to restore, and to then give then REAL value.
H. A WORLD FULL OF
There are huge piles of old
electronic gear which many people wanted me to repair so it
works as well as the day they
purchased it between 10 and 75 years ago. But like any good
doctor, I could only do what is
possible. The impossible was no easier even with the help of
And I had to survive
economically, and you didn't offer any kind of good financial
You see, most
ppl who brought their JUNK to me for a fix had modern
expectations of NOT having to
pay more than $100 for any repair of anything older than 2
years. People forget just how expensive a
large floor standing radio-gram was in 1960, and forget how much
labour went into their production.
A full Quad sound system from 1957 with 2 mono Quad-II amps and
No22 preamp and AM and FM
tuners and a pair of ESL57 speakers was utterly unaffordable by
90% of the population.
Many parts used then cannot be sourced now, so whatever is done
becomes a modification
of existing, to make it safe, reliable, and better sounding and
compatible with other modern
gadgets such as CD players, sound cards, i-pods, portable hard
People with old junk needing a fix always seemed to think
today's repair personnel should work for
$20 a week, not a bad wage for 1960. But tradesmen NOW charge
maybe $100 per hour or more
for repairs to washing machines, fridges, cars, plumbing,
drains, electrical, so WHY do YOU expect
a 50 hour radio repair should cost only $100???? The repairs of
anything from the past is always
labour intensive, even a snapped dial cord in an AM radio may
take at least 2 hours to fix, and inevitably,
something else or many things will be found that need a fix.
The general public has very inconsistent ideas about a socially
just wage. For their work,
they expect at least the Australian median wage level 2013 of
about $35 per hour gross, plus perks
and conditions, ie, $72,800 per annum, but they hate paying a
radio guy $3 per hour.
The majority of my customers never insisted they pay by the
hour, only by the con, and because I
was desperate to eat, I politely accepted, because I could not
do anything much else.
Now I have the old age pension it pays so much better than the
60hours a week i used to work,
and customers now wanting to pay slave labour rates can all get
anyone want anything other than what I have outlined here, and
not be willing
to pay, or to learn to repair their own junk, I suggest they
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