ADVICE YOU MAY FIND USEFUL :-
I retired from repair work in 2012
because of health reasons and because the
old age pension paid much more than 40 hours repairing
I do not do any repairs, re-engineering, or custom building of new
You may need to be able to do very basic diagnosis of your
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
(3) Make sure you have connected wires to speaker and amplifier
with red or marked speaker wires to red terminals, and black or
unmarked wires to black
(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.
ARE THE 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
TURN ON the amp, and if the speaker is silent, then probably the
speaker has a serious fault.
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 FAULTY?
(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 channel.
(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
(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 tuner 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.
B. TURNTABLE and VINYL REPLAY.
Most TTs have rubber drive belts which degrade over time. There
are cheap generic belt
replacements with a range of belt section profiles, square,
circular, rectangular and a range
of belt lengths available from wescomponents.com.au
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
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 hardening 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
Ph +61 (02) 4328 1108
Mob 04 888 0801
Fax +61 (02) 4329 5383
104 Carrington St, Narara, NSW 2250.
Nerida is excellent to deal with via mail order and the minimum
stylus cost is about $50, with
a maximum far higher.
in 2018, I don't know if she is still operating.
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
However, the fitting of replacement cartridges is often beyond an
owner's capability because
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 intermittent
Not all TTs have easily replaceable cartridges, and many such TTs
are simply not worth trying
to restore, as they will never be better than the awful low cost
rubbishy TT one might buy
from 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 became common.
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
If there is no means of down force adjustment, you have an awful
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 speed.
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 PLAYERS.
These have become dinosaurs, except for hundreds of people with
hundreds of cassettes,
some going back to 1975.
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 at....
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 6295 7444
I have no idea if they have any service in 2018
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 things"
at the front panel of a speaker when the fabric cover is removed.
Between 1994 and 2004,
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 of
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
available from wescompoments.com.au
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
E. AM RADIO.
I sometimes repaired tubed AM radios or radiograms from 1950s or
Some had small Bakelite cases while others had elaborate veneered
timber in large floor
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
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
circuitry of the radio with a custom made "ferrite rod antenna".
The ferrite rod is a 10mm dia rod about 200mm long and made from
iron based material
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 coincide
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
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
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
low, whatever low is.
not including any repairs to the unsightly condition of timber,
Bakelite or plastic case.
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. Most
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 to my
page on Radio-re-engineering.
F. FM RADIO.
AM/FM radios 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 modern
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
labelled 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
Most solid 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 replace
modules or the whole radio if there is a fault.
G. 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 OLD JUNK.
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 angels.
And I had to survive economically, and you didn't offer any kind
of good financial offer.
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