AR8600 bulletin page

The bulletins contained on this page are not generally intended for self-fit, they generally represent 'dealer assistance'. Fitting of the optional filters, optional battery and enabling of I.F. output is intended for action by workshop technicians. No liability is accepted for damage caused by inexperienced personnel.

The PDF information requires Acrobat Reader to view and print, a free copy is available from the
Adobe web site http://www.adobe.com/

A new feature of MEMORY CLEAR has been introduced to the MK2 version (latest production 2003). If you switch the MK2 receiver on with the SCAN button depressed until the power-on message has ended, all memory channels will be deleted permanently (useful if you need to dump the frequencies in a rush). The search data and other programmable data is left intact.

Caution: If you press SCAN before the power-on message has disappeared, there is a chance that you will accidentally delete all you memory channels! We know this accident has happened already to a few customers :-(

The new feature also applies to the AR8200 MK3 receiver. The change is a response to public request, earlier production receivers cannot be updated (it would require a change of CPU which employs 'miniature pitch soldered' mounting, this is not cost effective to replace - it is not simply FLASH upgradeable). This addition is in line with AOR's commitment to ongoing product development.

The RS232 "clone of data" between two AR8600MK2 receivers using a connecting lead via the RS232 sockets is no-longer supported. The feature was removed early in the production of the MK2 version. Experiments suggest that the MK1 and early MK2 will still clone with latest MK2 production, but two later production MK2 units will not exchange data.

The latest Japanese operating manual for the MK2 no-longer carries information about the feature, the international English manual has not been amended so far.

It is still possible to clone the data using the optional EM8200 external memory slot card.

The AR8600 Mark2 has been introduced during June 2002. The main RF PCB is completely revised, it is not possible to update a Mark1 to a Mark2 by simple component change... the frequency coverage has also been extended with a revised CPU being employed.

The AR8600 is provided with a rear BNC socket which provides 10.7MHz I.F. output. The bandwidth is about 2MHz and our workshop measurements using WFM mode suggest that a positive gain exists between aerial input and I.F. output of 35dB to 40dB across the frequency bands.

Out of the carton box, I.F. output is limited to WFM mode only to minimise the effects of internal spurii, as the WFM oscillator is used to produce the 10.7MHz I.F. output. If you wish to obtain I.F. output in ALL MODES, please refer to the associated bulletin (Acrobat PDF file) - click here.

While the AR8600 may be used with either the SDU5000 or SDU5500 is passive mode, the RS232 communication with either spectrum display unit is not supported.

The AR8600 is internationally distributed with an English language operating manual apart from Japan where a Japanese language manual is provided. You can download it in three sections as Acrobat PDF files from the AOR UK operating manual page.

International distribution and support is formally the responsibility of AOR Japan, however each national distributor is responsible for generating and providing local language operating manuals... the local distributor then holds copyright to protect their investment. A list of international distributors is available from the AOR UK web site.

The German distributor Boger-funk advise us that they can provide a printed operating manual in German language, please contact them for charges.

We have encountered two AR8600 which have suffered damage due to over-voltage power being applied to the power socket (20V), one via an unregulated power supply and the other by vehicle connection. Here in the UK we only supply 12V & 15V ‘REGULATED’ power supplies for the AR8600 (UK manufactured)... we cannot comment on power supplies provided outside of the UK.

In both cases, the voltage regulator on the CPU PCB IC410 (TK11245) had failed, which in turn had damaged the EEPROM memory store IC402 (AT29C512) on the same PCB. This resulted in spurious behaviour and the inability to change memory contents.

Both components had to be replaced, and it is suggested (by AOR Japan, the equipment manufacturer) that two additional diodes (1N4148 or 1SS1588 or 1SS266) are inserted in series with the un-switched 12V line between connector J403 and the regulator IC410… this is best achieved by a cut in the track between the unused +ve pad of C426 en-route IC410. It is likely that the ‘system data’ may need to be reinstated after component replacement, using a modified version of the EM8200 slot card (referred to as an AR8600 workshop tool).

Additional series diodes have been fitted to all new stock equipment in recent months to increase robustness of the power supply circuit (for occasions where an over-volt connection is encountered).

If you require further clarification, please request that your supplier pursues the matter through their ‘distribution chain’ of supply as this level of information falls outside the scope of a simple technical bulletin.

If you have the optional internal NiCad battery (BP8600) fitted, the low battery indicator circuit may not function when the above modification is applied.

The change in value is due to the voltage drop presented by the series diode. The indicator should turn on when the battery voltage drops around 8.2V to 8.3 V. If you are not using the internal battery, ignore these component value changes. If you do not change the components, no damage will occur, the set will simply stop working when the BP8600 battery runs flat - without warning.

Initially designed to provide up to two hours of operation, tests have shown that once the internal battery has been fully charged using an optional 15V regulated DC power supply, the monitoring time extends to around FIVE HOURS (with back-lit LCD lamps off).

Note: Operational times are for guidance but depend upon the style of operation (volume level, backlight, scanning etc) and are not guaranteed.

If your AR8200 is behaving strangely such as locking up or powering down unexpectedly, it may be suffering from corrupt data (programmable data or system data or both) due to a power glitch (a.c. supply interruption, battery low etc).

The corruption can affect the search bank, memory bank (or channel) or indexes such as pass list of select scan list. Instead of the data reading (for example) 123.450 MHz, it will attempt to read 123.zv0 MHz... as the corrupt data
is not recognised, it caused the AR8200 to 'crash' - like a computer program.

If the problem persists, it may require the system data to be refreshed using a modified version of the EM8200 external memory card (which allows system data to be written). If you already have an EM8200 card, your supplier may be able to arrange for the EM8200 to be modified and loaded with default data (so the recovery procedure will be just a couple of key presses). Please contact your supplier if you are unable to progress the matter.

AOR UK is simply the distributor for the UK & Ireland, the AR8200-2 has been manufactured by AOR Japan who are also responsible for international distribution and support:

Following a report by Bob Farish (direct and via the internet) we investigated a report that memory data was being lost when using the AR8600 with the EM8200 external memory slot card.

No problems are experienced if 'all memories' are used.

If a single memory bank is loaded to the slot card , it is stored correctly.

If the single memory bank is loaded back to the set, the memories and individual text comments are re-loaded to the set correctly but the overall 'bank' text comment is not re-loaded (this appears to be the case regardless of if the set is in scan, search or VFO).

However if the set is being used on a different memory bank to that being re-loaded from the slot card, the overall bank text comment is then correct for the re-loaded bank, BUT, the bank that the set was being used on then gets labelled with whatever text comment was previously in the bank being overwritten.

This only happens in the AR8600 (mk1 & 2). It isn't a problem in the AR8200mk3.

Inconsistencies have been reported to us regarding the operation of the RU8200 record / playback option with the AR8600 (particularly in continuous loop mode), neither the AR8600 operating manual or RU8200 product leaflet are 100% accurate. The revised section of the operating manual is presented here, the main areas of charge are highlighted in red colour:

Once the slot cards have been fitted, they must be registered for use via the slot card menu. This is because only one slot card from GROUP 1 and one slot card from GROUP 2 can be used simultaneously, registering the slot cards is a way of managing their use.

The optional slot cards must be REGISTERED via the SLOT CARD OPTION MENU before they can be manipulated via their own control menus. To access the slot card registration menu option menu PUSH [FUNC] PRESS [CLEAR]

The menu is presented in two sections (pages), the first covers the slot cards in GROUP 1 (TE8200, CT8200, VI8200) and the second page covers the slot cards in GROUP 2 (EM8200, RU8200).

The UP / DOWN arrow keys are used to move between lines representing the slot card fitted, if you do not have the listed card fitted, you will not be able to move to the displayed line, it will be skipped.

For example, if you have the TE8200 and VI8200 slot cards fitted, pressing the DOWN key will skip over the CT8200 selection line, the second page containing the EM8200 and RU8200 entries will also be inaccessible. The UP key may be used to move backward through the menu items. Ignore the “AUT” legend if displayed on the LCD.

When the cursor is flashing on the desired line for the required option, use LEFT / RIGHT arrow or [PASS] key or MAIN DIAL to REGISTER or DE-REGISTER the option as a toggle. When registered, the legend ‘STAR’ will be displayed on the LCD next to the slot card description. Remember, you may register one slot card from GROUP 1 and one card from GROUP 2 for simultaneous operation if desired. To complete the selection, PUSH [ENT]

The RU8200 enables around 20 seconds of audio to be recorded to a chip within the RU8200 for playback at a later time. The chip may be used to recorded over and over again overwriting the previous recordings. The recording may also be played back over and over, very useful if you have grabbed an interesting recording! It is also possible to set the RU8200 to continuously record the last 20 seconds of activity ensuring that an interesting transmission is never missed. The RU8200 may be used in VFO, scan, search but note the following:

VFO mode: The RU8200 operates as laid out here, recording starts when the squelch opens or records immediately if the squelch is already open. When recording has started, manual operation of the front panel squelch control is disabled. The RU8200 is best suited to use in VFO mode.

SCAN / SEARCH mode: The RU8200 will start recording when the squelch opens but recording will stop immediately once the squelch closes and the receiver continues scanning or searching. As the recording has been deactivated when the receiver moves to new channels, accidental overwriting of the recording is prevented. If however you want to record every active channel that the receivers finds, select CONTINUOUS from the record menu. In CONTINUOUS mode, when the receiver stops on a busy channel, the recording will start automatically, however when the receiver moves to another channel (automatically during scan & search), the previous recording will be stopped and a new session started - speedy manual intervention is required.

Insert the RU8200 slot card and switch the AR8600 on and REGISTER the RU8200 card via the OPTION SELECT registration menu. Refer to section 18-2 and the example for the TE8200 shown in section 18-3. Remember, the RU8200 is listed in group 2 of the slot card option list.

Insert the RU8200 slot card and switch the AR8600 on, select VFO mode. PUSH [FUNC] PUSH [CLEAR] to access the RU8200 menu. The AR8600 will present the record / playback menu. The legend “RECORDER” confirms selection of the record & playback menu. PUSH the [PASS] key or use the main dial or LEFT / RIGHT arrow keys to toggle between “REC” (RECORD), “C.REC” (continuous record) and “PLAY” (play).

PUSH [ENT] to accept the selection and return to the previous menu or PUSH [CLEAR] to abort. Recording and playback can be carried out while the AR8600 is in VFO, scan or search mode.

While in the record & playback menu select “REC” and PUSH [ENT]. The LCD will return to its previous display with the legend “REC” in the bottom left corner of the LCD to show that the RU8200 is active. If the squelch is currently open, recording will take place immediately, otherwise recording will take place next time the squelch opens.

While recording is in progress, the second line from the bottom of the LCD (usually displaying the standby frequency in 2VFO mode) changes to a progress bar “REC =====>” indicating that recording is in progress. Once started, the recording process continues for about 20 seconds and the legend “End” is displayed when the recording process is complete. Once started, recording continues even if the squelch closes but you may PUSH the [CLEAR] key half way through a recording to stop it from recording 20 seconds of nothing! PUSH the [CLEAR] key after recording has ended to clear the recording related text from the LCD.

To enable continuous recording of the last 20 seconds, select “REC” while in the record & playback menu select then PUSH [ENT]. The LCD will return to its previous display with the legend “REC” in the bottom left corner of the LCD to show that the RU8200 is active. If the squelch is currently open, recording will take place immediately, otherwise recording will take place next time the squelch opens. When the 20 second recording process has completed, recording will simple start again from the beginning forming a loop.

Note: RU8200 recording is disabled when the band scope facility is operational.

It is assumed that you have already made a recording. While in the record & playback menu select “PLAY” and PUSH [ENT]. The LCD will return to its previous display with the legend “PLY” in the bottom left corner of the LCD to show that the RU8200 is active. Playback will start instantly.

While playback is in progress, the second line from the bottom of the LCD (usually displaying the standby frequency in 2VFO mode) changes to a progress bar “PLY =====>” indicating that playback is in progress. Once started, the playback process continues for about 20 seconds and the legend “End” is displayed when the playback is complete.
You may PUSH the [CLEAR] key to cancel playback or clear the recording related text from the LCD.

Note: No liability in any form will be accepted in respect of recordings made using the RU8200 option.

We have received two reports of lack of SSB reception with the AR8600 series, either USB or LSB failure. On both occasions, the problem has been traced to failure of the SSB resonator with simple replacement clearing the fault.

Remove bottom chassis cover (3 black, threaded screws in centre of board from top and 6 screws from bottom).

Looking from the front, top of the AR8600, the SSB resonators are located in the front, right hand corner of the set.

If one has stopped oscillating, before replacing it, check that none of the surrounding devices have any dry or failed joints.

In practice, alignment of these devices will not have been set up too critically and will probably not require much alignment.

In practice, if the set is up to working temperature and is known to be aligned very closely to correct frequency at a spot frequency, then the trimmers can be aligned by ear for correct sounding audio on SSB using either a known SSB transmission of the side band or a known AM signal. This will only work if the set is close to actual frequency. If it is not, it will either be impossible to adjust the trimmers far enough or the resultant audio tone when switching between side bands will be markedly different (even just on background noise).

All of this is of course far easier if a frequency counter (and signal generator) are available.

The procedure is the same as above for the mark 1 sets with the following differences;

Viewed from the front of the set, the resonator location is on the right hand side of the set about half way back.

The ASM8600 has been introduced in 2003 with commercial operators in mind. It simply plugs into the ACC rear panel socket of the AR8600MK2 where serial numbers are above 072661, it cannot be used with the AR8600MK1.

Where the AR8600MK2 serial number is below 072661 a small modification is required:

1. Replace R396 220 ohm with a new resistor of 100 ohm.
2. Replace R349 100 k ohm with a new resistor of 4.7 k ohm.
3. Add a new 330uF/6.3V electrolytic capacitor in parallel with C361 1uF. Glue the new capacitor to the printed board.
4. Add a new insulated wire (140mm long) between C361 and pin #5 of CN2 connector. Fix the new wire at two points by glue on the printed board.

A posting on the AR8600 Yahoo group reported negative-going audio spikes on the tape output line when the squelch closes. The report has been investigated in the UK workshop and our findings have been posted back to the group and copied to AOR Japan (AR8600 designer & manufacturer). The UK engineer's comments are given here as a small component change addresses the issue... largely related to voice operated tape recorders [25.09.2003].

The audio on pin 6 and 7 of the accessory socket is a straight audio feed, the mark 2 being squelch controlled. The audio out of pin 2 is straight from the detector. It is not muted but is only usable on the 'narrower' FM modes (Presumably this is no use for VHF ACARS needing AM demodulating - where the discussion originated?).

Using the audio outputs on pins 6 or 7, the full audio signal is present. On the mark 2 set when the squelch is used, once the signal disappears, the output on pin6/7 mutes apart from a series of -ve going spikes which eventually disappear.

If a sensitive voice operated tape recorder is used, this may be seen as audio and continue recording.

The audio is fed to pins 6 and 7 via op-amp IC52, capacitor C407(1uf/10v) switching IC51. IC52 is running with quite a high gain. This isn't a problem with a signal present but it easily hits its voltage supply levels at the output with no signal present (very noticeable on noise on NFM). In itself, this isn't a problem.

This signal then passes through the 1uF capacitor where it is, in effect, DC blocked from the op-amp. The noise signal which was previously centred around half supply level (2.5v) and swinging to 0v and 5v now becomes referenced at a slightly lower level. The resultant signal level swing now goes below 0v (at least until the DC voltage across capacitor levels out a little after the mute is switched in).

The signal then passes through the mute switching (IC51). It appears that the switching IC only operates satisfactorily when the input voltage is at 0v or above.

The result is that the larger sections of negative going signal passes through the IC as a negative spikes (down to about -1v). The spikes disappear as the capacitor voltage balances out. This is what appears at pin 6 & 7.

1) The gain of the op-amp can be reduced by reducing the value of R392 (220k) feedback resistor. This stops the noise signal hitting voltage supply levels at the op-amp output so easily. The drawback being that the audio output of a wanted signal will be reduced quite a bit.

2) Move the position of the blocking cap (C407) to after the mute switching. This is a 100% fix. The only drawback I can see being that the switching device is now switching a slightly higher level of DC as well as the audio signal. I don't believe that this is a problem as I'm sure that this device is often used to switch small current DC levels.

To do this. Lift C407 from the board and bridge its pads with a wire link. Cut the track out from IC51, pin 1 and bridge the gap with the capacitor (+ve mark towards IC51). Pin 1 is the front left hand pin of IC51 which feed the 100k resistor and R397.

Comment added 26.09.2003: If you are using FM mode, the detector / discriminator out is free from clicks, but this cannot be used for AM.

Output from the detector / discriminator pin of the AUX socket is generated in all receive modes because the FM chip is active all the time - irrespective of receive mode. This means that the detector / discriminator output is unusable (due to very low level and distortion) in receive modes other than FM.

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.

AR8600MK2

		RX	SINAD	IM3	IP3	NF	10.7MHz IF_OUT
	Condition		(12dB)	(+50/+100KHz)		(BW=16KHz)	(RF=-50dBm)
	UNIT	MHz		dB	dBm	dB	dBm
		19.9	-123	72	-15.0	-1.0	-48
		40.5	-120	81	1.5	2.0	-52
		109.5	-120	78	-3.0	2.0	-52
		479.9	-120	75	-7.5	2.0	-51
		999.5	-119	83	5.5	3.0	-52
		1999.5	-103	85	24.5	19.0	-54
		2699.5	-99	73	10.5	23.0	-53

	PLL LOCK TIME			RX 1MHz -> 3000MHz :			75 mS
				RX 3000MHz -> 1MHZ :			32 mS

AR8600 Bulletin Page