928-533-9666   
TM
We Keep Your Classic Car Sounding Classic!
Rated
Rated
Bonded
FCC Licensed
Bonded
FCC Licensed
Sorry, NO
calls for belts!
Sorry, NO
calls for parts!
Fins on
left side
Buttons above
dial/tape door
10" wide
3 - 3/4" high
10" front/back
Early '70's Delco AM-FM-8 Track
- an Endangered Species
This model is a special case in which we consider it ethical to warn the customer beforehand of the potential risks
involved in having this model restored.  Currently, there are a full dozen parts that are no longer available except
from a similar unit which, due to their cost and scarcity, are not cost-effective or even possible to keep on hand.

In addition, this unit is extremely time-consuming to take apart safely, and impossible to operate with power applied
for troubleshooting without  extending some 40 wires to keep the circuit boards from shorting against the tape
transport.  The parts which are no longer available are also, unfortunately, the parts more likely to cause eventual
failure and possibly render your unit unusable unless you're lucky enough to find a spare parts unit.

The following failures can occur after you've paid to have the unit restored, and
are never covered by any type
of warranty, regardless of what work was performed:


Tuner Assembly

Consisting essentially of rods of a very brittle material called ferrite being pushed into or pulled out of coils wound
on a fiberous core with very tight clearances, the tuner assembly can be prone to damage from the effects of age,
temperature and moisture:  The ferrite rods begin to rub against the fiber coil cores (which have expanded from
moisture), eventually pulling the entire coil out of its housing and breaking the tiny wires beyond repair.

Per the service manual, the tuner assembly cannot be field serviced and no instructions are provided.


Left and Right Audio Amplifier Chips

The Delco DM-8 represents most of the audio preamp and driver circuitry, and yes they do sometimes fail.  With
some time, research and experimentation, we hope to eventually fabricate a substitute circuit which will fit.  At
this time, development has not yet begun and we cannot include these chips in our warranty.

Left and Right Driver Transformers

Made from many turns of wire around an iron core, the driver transformers match the "impedance" of one
circuit's output to the input impedance of the next for maximum signal transfer.  And since different signal
levels tend to be at different voltages and currents, transformers also isolate one circuit from another.  The
audio transformers in this model are physically very close to the output transistor heat sink, which gets too
hot in operation to keep your hand on.  Thus, over the years the ambient heat can break down the thin layer
or insulation on the turns of wire in the transformer, causing turns to short together which burns it up.

Due to the way a transformer is constructed, they can often be rewound with new wire.  This procedure
requires that we literally unwind a known good transformer, noting the wire size, number of turns and where
the taps (if any) are located within each winding.  Again, this is something we have not yet attempted - and
because actual practice does occasionally violate electronics theory (that is where "mods" come from), we
cannot be certain of our ability to replace transformers until we have made and fully tested one.  We expect
to have many transformer issues solved near the end of 2015.  Until then, we cannot warranty transformers.

Left and Right Output Transformers

Exact same situation as above - except that output transformers handle more power and fail more often.

DM-11 Quadrature Detector

An early integrated circuit - failure kills the FM.  No one will ever devise a substitute for this part.

DM-14 Multiplex Detector

Exact same situation as above.  At their age, these chips can blow from simply turning the unit ON.

Volume/Tone/Track Change Control

These are very delicate - and damaged from poor packing techniques WAY too often

Tuning/Fader Control

Same as above.  Even if they are only slightly bent, they are more likely to BREAK than straighten.

Pushbuttons

Broken off by careless packing - that is, throwing this 15 pound hunk of steel - with very thin and brittle
plastic buttons sticking out - into a flat rate box and expecting a few peanuts to protect it.  
DUH!


Special Conditions For This Model

Due to the parts availability issues, the tremendous amount of time required to strip the unit down to a
serviceable level and potential of future customer disappointment, WE PREFER NOT TO SERVICE THIS MODEL.
It's possible that the FM section can go out completely - shortly after you paid for the restoration - and
would
not be covered by warranty or even reparable
.  Same applies to the audio chips, transformers and all failures
caused by any parts described on this page.

We can offer some consolation:  The entire 8 track section is fully guaranteed.  Motor, track change function,
tape head preamp, and production of sound UP TO the audio board.  CAUTION:  The audio chips process the
audio after the 8 track or radio complete their tasks - BUT a bad audio chip kills the 8 track signal on one side
as well as the radio, and is not considered part of the dedicated 8 track section since it also works with the radio.

In short, having this model restored presents a slight short term risk to the customer, and a VERY HIGH long
term risk.  The chips and transformers in these units are destined to fail at one time or another - as mentioned
previously, the chips can blow from simply turning the unit on one too many times due to their age.

Thus, we must be extremely strict about our warranty terms on this model, in contrast to our normal policy of
performing most post-restoration work at little to no charge to promote overall positive relationships.  In the
case of this model, we are simply unable to repair non-warranty issues due to parts availability and cost.

Our minimum fee for BASIC restoration on this model is 495.00, with a FOUR MONTH turnaround.  If there is any
disagreement at all about our turn times on this model, we prefer to pass on the job.

Back to "Pricing" page
Sorry, NO
calls for belts!
Sorry, NO
calls for parts!
928-533-9666   
We Keep Your Classic Car Sounding Classic!
Sorry, NO
calls for belts!
Sorry, NO
calls for parts!