AR3000 bulletin page

The AR3000 receiver with serial numbers below xx600 are no-longer serviced. Parts are not available from the manufacturer and the boards have become unreliable with age leading to intermittent and repeat failures.

Both the AR3000 and AR3000A reset is the same manner (but the switches are in slightly different places). Remove the bottom case half, the reset switch is located on the rear of the front CPU board. The required switch is the small momentary push switch located next to the round-black bleeper (not the slide switch which sets RS232 baud rate). With the set connected to power and the on/off switch on, push this switch, hold for one second then release. The reset will take a short while and all LCD characters will appear for a few seconds. When the reset is complete, the AR3000 reverts to its normal operating mode (clock set back to zero, memories back to factory defaults etc).

When battery voltage drops below 2.80V (using a DVM) it is time to replace the battery... its nominal voltage is 3.0V The battery is a solder type CR2032 and is available from UK stock priced at £4.82 including postage and VAT, the part number is: W09203205/ I12

The memory back up battery can be replaced quite easily with the use of screwdrivers and a soldering iron. This involves removal of the top and bottom case halves (6 screws) and the front panel (4 screws). With the CPU board exposed, the battery can be located behind it on the right hand side. This is best de-soldered from the front of the board in between the keyboard switches. Care must be taken not to short the new battery when fitting it and check that the polarity is correct (+ & - are marked on the board). Carry out a micro reset once the new battery has been fitted as it is possible for the unit to be in a crashed state and a higher than normal amount of current may be drawn, shortening battery life.

If you are left looking at a small black plastic gate, it has fallen out from the space between the front panel of the radio and microprocessor PCB. Look carefully at the gate, you will notice that there is a cut-out... this is to enable the gate to fit roughly in the middle of the microprocessor PCB with the cut-out facing the PCB so that it sits flat against the board, avoiding the raised solder contacts. The gate appears to be a mechanical protection device to prevent the front panel from smashing into the microprocessor PCB if a very heavy blow is encountered. Occasionally the gate causes poor mechanical operation of the keys... if so, slacken the four screws which hold the front panel in position, manoeuvre the panel and re-tighten the screws so that the keys operate smoothly. If you cannot achieve positive action of the keys (or can't work out where to place the gate), throw the gate away! Occasionally the gate is omitted during manufacture. The microprocessor PCB has five holes for the screws to secure it to the metal chassis, however there are usually only four screws fitted (don't look for the missing screw under your chair, its not there).

Of course we are happy to repair your receiver in our workshop. Our workshop rate is £33.00 per hour + VAT with 95% of repairs being carried out within the first hour on the bench. Parts are provided at trade cost, return carriage & insurance extra, the total would be about £50.00 based on the assumption that the battery is to blame.

If your battery does not look like the picture shown here, you may have an early serial number unit, call to discuss the situation.

When setting the time on the AR3000 a potential exists for the microprocessor to CRASH.

This is a nuisance, you may loose the memory contents and have to internally reset the microprocessor using the RESET switch on the reverse of the keypad. To ensure this does not happen, simply press the [DIAL] key after completing the time input terminating in [ENT]. The problem arises when you attempt to change mode before pressing [DIAL]. This is simple but effective and may save hours of reprogramming!

A pre-amp is fitted to the 3000 models for use over the short wave range (100kHz to 30MHz). This is normally switched on. If additional attenuation is required or mixing problems experienced (using large antennas?) then turn the pre-amp off. The switches for this are located under the top cover (both covers will have to be removed) on the front, left hand side. The switches have to be either both ON or both OFF for receive to be possible. If your set appears very deaf below 30MHz, check the position of these switches. - It wouldn't be the first time we have seen a set returned with a reported "no SW RX" due to one switch being ON and the other OFF.

If the receiver squelch becomes intermittently OPEN regardless of squelch control position and changes with mechanical movement of temperature, the unit may be suffering from a cracked surface mount component on the i.f. PCB.

Have a look at the solder side of the PCB (the i.f. PCB is the bottom board), you will need to temporarily remove it from the radio.

Look on the opposite side of the board to the ceramic resonator marked CF2 (usually orange in colour). There are usually two added conventional components, one being a resistor (12k) and the other a disk ceramic capacitor (possibly green in colour) with a value of 102 (1000pF).

The capacitor is attached to a 3-pin device at one end and is soldered between a SMD resistor and SMD capacitor at the other... the capacitor may be cracked ??

Temporarily lift one leg of the disk capacitor and see if the SMD capacitor falls in two !

Replace the SMD cap (size is 0805), the value is 103 (C170)... in 'real language' this is 0.01uF or may be expressed as 10nF.

One one occasion, it has been reported that another SMD capacitor C82 (103 / 0.01uF / 10nF) was also faulty resulting in confusing squelch problems, this capacitor is situated just one component away from C170, only R190 separates the two components.

A picture of the underside of the IF PCB with close-up of the components is available as a single page Acrobat PDF file (196kB) - click here.

The surface mount 5V regulator IC10 (S-81250HG), runs constantly if power is connected to the unit. It provides the main supply to the microprocessor board and also the back up supply when the power is still connected but the unit not switched on. This prolongs the lithium back up battery life.

The regulator should be able to run constantly for the entire life of the set without problems if required. Occasionally one may fail and require replacing. This is however very unusual and is most probably due to a ‘push’ from some other source. e.g. having to dissipate the extra heat from using a higher than normal voltage power source or some other failure within the set drawing extra current from the 5V line.

If the device fails, the symptoms are that the unit will not power up and the clock is not displayed at all. Don’t get this confused with a crashed microprocessor, as symptoms can be very similar. A re-set, however, will not cure the regulator fault. A failed internal fuse will also give similar symptoms.

Check if the regulator has failed by connecting power (power switch on or off) and measuring for 5V at pin 1, connector J9. These are located on the multi-pin connector close to the remote socket and are clearly labelled. For information, viewed from the top of the SMD device (IC10) with three legs to the left, the designations from top to bottom are G, V-in, V-out). Remove the power again.

Remove two mini coax connectors (J3 & J10) from the left-hand side of the board. Note that these are quite easily damaged and it is best to remove them with a straight upwards pull with a pair of pointed pliers (don’t lever them sideways as the centre connection will be damaged).

This allows the board to hinge towards the rear of the set without removing any further connectors.

Again, looking from the front of the set, IC10 is located on the solder side of the board near the left-hand edge. It is positioned between the screw head (holding regulator IC11) and the side of the board.

Hold the soldering iron on the single leg at the other side and lift the device clear of the board with a pair of fine pliers.

If the device does not lift, do not force it as the tracks may pull away. Try de-soldering the legs again.

Take care not to trap any wires when re-fitting the PCB. Take particular care if the unit is a plus set as several more wires pass down the right hand side of the set.

Note: when re-fitting the connectors, they usually fall back into the correct place. If they don’t;

Before fitting the case, connect power to the set and check that 5v is present on pin 1 of J9. Now refit the cover and test the set.

The replacement LCD is no-longer available, last stock was sold in March 2002 and AOR Japan have no more stock (the manufacturer).

NOTE: November 2003, a small number of LCDs for the AR3000 have been supplied by AOR Japan. Availability first come first served, contact us for price etc.

Two approaches have been taken by customers, either modify the unit to accept the LCD from the AR3000A (the LCDs have a different number of pins, different legends and are a different size) or locate a scrap radio to transfer parts across. It is possible to fit the CPU PCB from the AR3000A to an AR3000, a technical bulletin on the subject exits - but has not been originated by AOR.

The circuit areas of AR3000 / AR3000A CPU / LCD have been scanned at 600dpi and exported at the same resolution to an Acrobat PDF file (359kb), the quality of reproduction is still not great click here.

If fitting the CPU board from an AR3000A into an AR3000, have a look at the following page which described what work is required:

http://www.mods.dk/mods.php3?model=ar-3000&radio=aor

One customer who transferred the LCD made the following comment: I have successfully converted my AR3000 to a AR3000A with the new CPU PCB and want to change the click type VFO dial to smooth one. There was one other mod to do also, the ATT function stopped working with the new CPU PCB. This is fixed by changing the factory mod on the AR3000 Front end PCB. There is an latching IC that I cant read what part it is on my circuit, but the new pin the ATT is connected to is pin 7. Looking at the PCB this pin was connected at manufacture but then mod at the factory to another pin on the same IC. Sorry I can be more exact but my text on the circuit is blurred, just look on your circuit to where the ATT is latched from.

It is possible for AOR UK to provide a screened RS232 cable for the AR3000 and AR3000A, they are made to order in the UK workshop:

a)	AR3000 for a 25 way COM port on a PC (PC3000-25)
b)	AR3000 for a 9 way COM port on a PC (PC3000-9)
c)	AR3000A for a 25 way COM port on a PC (PC3000A-25)
d)	AR3000A for a 9 way COM port on a PC (PC3000A-9)

[At September 2004, each lead is priced at GBP 12.00 inc VAT, P&P to a UK address is an additional GBP 2.00 inc VAT. The leads are around 2m in length, additional length can be provided at GBP 2.00 per metre (covers the cost of cable, extra postage and handling). We do not recommend leads longer than 10m.... also the longer the cable, the higher the potential 'noise' problem. Be clear to state AR3000 or AR3000A as the former requires an extra link wire between pins 1 + 7.]

Payment information is available from http://www.aoruk.com/payment.htm

AR3000/A 25 male plug required	PC 25 way female plug required
1 *	1 SCREENED CABLE only to PC end
2	2
3	3
4	4
5	5
7 *	7 SIGNAL GROUND

* If the AR3000 is in use, add a link between pin-1 and pin-7 on the AR3000 end of cable, not required for the AR3000A.

* If the AR3000 is in use, add a link between pin-1 and pin-7 on the AR3000 end of cable, not required for the AR3000A.

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Due to continuous developments, AOR reserves the right to make design and specification changes for product improvement without prior notice. The performance specification figures indicated are nominal values of production units. There may be some deviation from these values in individual units.

AR3000/A 25 male plug required	PC 9 way female plug required
1 *	1 SCREENED CABLE only to PC end
2	3
3	2
4	7
5	8
7 *	5 SIGNAL GROUND, also attach the SCREENED CABLE only to PC end

AR3000 Bulletin Page