AR800 bulletin page

The AR800 receiver is no-longer serviced. Parts are not available from the manufacturer and service costs equal or exceed the resale value.

It is a fact that older electrical equipment reaches an age where servicing becomes difficult and not cost effective. In particular, the solder connections, PCB and wiring become increasingly brittle. The following units are no-longer accepted for service in the UK workshop:

AR800E Hand-portable receiver, discontinued by 1990. Batteries no longer available from AOR (but see reference to battery re-manufacturers in the technical bulletin page).

AOR BP800 replacement NiCad battery

Unfortunately demand for this replacement pack has dropped to a point whereby its continued manufacture has become uneconomic. NiCads do not last for ever if stored on the shelf awaiting sale, for this reason regular manufacture and rotation of stock is most important.

For your information, the BP800 was available until the end of January 1995 as a sales item, price was £17.50 including VAT with P&P being extra.

The battery comprises of 4 cells, two in each cardboard tube (physically strapped together), soldered in series to provide a total nominal voltage of 4.8V, the cells are 'round about two-thirds the size of an AA cell' each, the capacity being 450mAhr. A two pin connector (red/black) is used to connect the battery to the radio, however this part is no longer available from stock... it is not too difficult to solder the wires directly to the radio's battery connector.

It may be possible to have batteries manufactured /re-manufactured here in the UK by one of the replacement battery manufacturers:

AR800E - Intermittent or no NFM.

This is quite a common problem with the AR800E. It is usually caused by the failure of T201 (quadrature coil/transformer).
This component is positioned next to the battery pack and is prone to damage if the set is subject to any physical shock.

To replace T201: Remove the battery cover and battery pack. Remove the two screws holding the board resting inside the rear case. This PCB can now be worked on but it may be a good idea to also remove the further two screws and rear case to prevent damage to them.
Be careful not to break the wiring to this board.

T201 is the small metal transformer located on this board next to the battery pack slot and IC200 (MC3361). A small amount of adjustment for best quality receive may be necessary once the new transformer is fitted.

AR800E - Failure of input resistor.

A 10ohm 0.25W resistor is fitted in-line with the charge socket on the AR800E to limit charge current into the battery pack. This can fail under any condition in which the charge current increases abnormally. Usual causes are trying to charge a faulty battery pack (s/c cells) or trying to charge the batteries from a 13.8V supply.

The common symptoms of its failure are lack of charge to battery pack or hot resistor smell. Although a simple fault, the resistor is quite difficult to replace due to its location between the charge socket and top panel controls.

To replace this resistor, remove the battery cover, battery and the two screws holding the rear PCB. Lift this board up to reveal the two further screws. Remove these and then the rear case The set should now be stripped far enough to see the failed resistor behind the top panel connected between the charge socket and power switch (it should be sleeved in plastic).
A failed component is usually accompanied by a slight melt mark in the plastic close to it. The set can be stripped further if necessary to replace the resistor depending on how steady you are with a soldering iron. Rebuild the set carefully. If the set now fails to receive, chances are, the mini coax wire between the two PCBs has become disconnected. Note that the shield to this wire is only connected at one end.

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.