Audio Dynamics 14635013 manual Intermittent hum, noise or silence are usually the result

If hum and noise are present to any unusual degree, first remove the inputs plugs from the Stereo 35, and replace them with short-circuited input plugs (or temporarily con- nect a jumper between eyelets 1 and 2 on each circuit board). If the hum and noise become virtually inaudible, the amplifier is probably working properly, and the cause should be sought elsewhere in the system. If plainly audible hum or noise persist, there may be an error or defective component in the power supply, or an open ground con- nection. If the hum is in one channel of the amplifier only, check to see that eyelet #2 of its circuit board is soldered to the input ground lug. Occasionally, a bad tube will cause this condition, which is easily determined by switching tubes until the hum appears in opposite channel. Hum on both channels is probably due to a power supply defect, a bad capacitor section or defective diode.

Intermittent hum, noise or silence are usually the result

of a poor solder connection. If the trouble occurs in both channels, check the power supply first; if in one channel alone, examine the solder connections on that side.

Filament glow is normal, but if the plate (the large metal area) of a tube tends to glow red, either the tube or its associated circuitry is faulty. It all four of the output tubes glow in this manner, there is a short circuit in either the cathode (pin #3 of any 6BQ5) or filament (pin #4 and #5), or at lug '#4 of the filter capacitor.

The voltage chart printed alongside the schematic dia- gram may be helpful in trouble-shooting. If readings made at any of the points indicated differ from those listed by more than 10%, it is likely that a wiring error or defective component is nearby in the circuit.

The Stereo 35 should never be operated with any of its tubes removed from their sockets.

FACTORY SERVICE AND WARRANTY

The Stereo 35 is designed to provide reliable, trouble- free performance for a long period of time. when properly assembled and installed. It is intended for use with the 120-volt a.c. power supplied to most homes. Although varia- tions of several volts above or below this figure will have no pronounced effect upon performance or component life, the normal guarantee on the equipment is not applicable if it is operated with a.c. inputs greater than 130 volts. If your local power is this high or higher in voltage, it is suggested that a voltage regulating or adjusting device be installed to protect the amplifier.

All parts used in the Stereo 35 are guaranteed for a period of one year from the date of purchase except tubes, which carry the standard electronic industry (EIA) 90-day warranty. Defective parts will be replaced at no charge if they are returned prepaid to the factory either directly or via the dealer from whom the kit was purchased. Many Dynakit dealers carry parts in stock which may be used for replacements. After the guarantee period has passed, Dynaco, Inc. will supply any non-standard parts used at net prices. Parts which are standard (resistors, capacitors, tubes) can generally be purchased from a local electronics supply store.

If it is believed that a transformer is defective, it should be disconnected by unsoldering, never by cutting its leads so short that it cannot be re-used.

If the kit has been completely assembled, yet cannot be made to function properly, or if difficulty is apparent after a short period of use, we will service the kit for a fixed charge of $6.00, plus the cost of the parts which are outside the warranty or have been damaged by the user.

Factory assembled amplifier include a one-year war- ranty on labour as well as parts.

IMPORTANT: FIXED-CHARGE SERVICE AND MAINTENANCE ARE NOT AVAILABLE FOR KITS WHICH ARE INCOMPLETELY WIRED, OR KITS WIRED WITH SOLDER OTHER THAN ROSIN CORE TYPE, OR KITS PHYSICALLY OR ELETTRICALLY MODIFIED WITHOUT PRIOR FACTORY AUTHORIZATION. ADDI- TIONALLY, NO PARTS WILL BE REPLACED AND NO SERVICE MADE AVAILABLE FOR KITS FOR WHICH THE WARRANTY POST CARD HAS NOT BEEN RETURNED . THE SERIAL NUMBER ON THE FRONT COVER OF THIS INSTRUCTIONS BOOK MUST BE MEN- TIONED IN ALL CORRESPONDENCE AND IN ANY CASE WHERE PARTS ARE RETURNED, OR KITS SENT OR BROUGHT TO THE FAC- TORY FOR SERVICE.

It is the factory prerogative to limit the service facility to one year from the date of purchase.

When shipping the amplifier to Dynaco, Inc., for service, attach a note specifying the symptoms, the name and address of the sender, and the serial number of the kits. The kit should be securely packed to withstand the abuses of handling in transit. It should be placed in a rugged car- ton surrounded by several inches of shredded paper or other soft packing material. The original kit carton is not

suitable for shipment of a wired amplifier.

Shipment should be made by prepaid EXPRESS, where possible, repaired kits will then be returned EXPRESS C:O:D: for freight and service charges (unless these charges have been prepaid). Parcel post is not a safe method for the shipment of assembled kits, and should not be used for this purpose.

The Dyna Company assumes no liability or responsibility for damages or injuries sustained in assembly or operation of this Dynakit.

STEREO 35 PART LIST

1	Chassis set	1	5-Lug Terminal Strip	HARDWARE
	(chassis, cover and bottom plate)	1	Fuse 2-Ampere Slo-Blo	4	Rubber Feet
1	Power Transformer PA-774	1	Line Cord with Plug	1	½" Grommet
2	Output Transformers Z-565	2	Input Sockets	12	8/32 x ¼" Machines Screws
4	Output Tubes 6BQ5/EL84/7189	1	Roll Hookup Wire	12	8/32 Nuts
2	Driver Tubes 7247	2	PC-13 Circuit Board Assemblies	12	#B Lockwashers
2	Rectifier Diodes 500 ma 1000 PIV (Silicon)			25	4/40 x ¼" Machine Screws
1	Quadruple Section Filter Capacitor	RESISTORS		25	4/40 Nuts
	60/40/20 @450 v.; 100 @ 25v.			25	#4 Lockwashers
2	3-Screw Terminal Strips	1	50 ohms, 5 watts	4	#6 Sheet Metal Screws
1	Fuse Holder with Rubber Washer and	1	95 ohms, 5 watts	1	Instruction Manual with Pictorial Diagrams
1	Circular Nut	1	6,800 ohms (blue-gray-red), 1 watt	1	Warranty Card

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