SOME 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 old stuff.

I do not do any repairs, re-engineering, or custom building of new audio systems.

You may need to be able to do very basic diagnosis of your problems..........

A. AMPLIFIERS.

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.

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 channel.

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
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 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 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 hardening with age.

There may be a replacement cartridge available for the old cartridge you have
from http://www.soundring.com.au
Email your TT brand and cartridge brand and all identification numbers to
Nerida, sales@soundring.com.au
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 long ago.

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
signals.

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 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 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....

http://www.artsound.fm/sound-restoration/
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

D. LOUDSPEAKERS.
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 repaired.

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 originals.

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 Miranda Hi-Fi.

E. AM RADIO.
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 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 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
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 band frequencies
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 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 from appliances.
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 Orchestra.
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 stuff.
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 beyond many.
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 non existent.

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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