To Fix an Old Ten-Tec Orion I Model 565
This is my Ten-Tec Orion Model 565 that was a very kind gift from a close friend (Douglas GD3RFK), I remember using the radio lots and for a while it was my main radio in the shack, I loved this radio and the noise reduction was legendary, but sadly with Ten Tec being somewhat shutdown, even though rumours and little hints of information kept appearing, the availability of parts and especially filters would be totally non-existent. It is a bit like another American company called Elecraft who basically dumped on all its owners of the K3 in stopping suppling parts for the K3 to anyone wishing to upgrade their great radios to as good as they could afford.
For me the Ten-Tec was such a great radio, I really wanted to upgrade to the 566 which had the colour display and quite a few other good upgrades, but I could never find one at the time.
Sadly back in 2014 I had a water tank in the loft split and dump its contents all over my office / shack, this was a very depressive time for me, I lost most of my computers, radio’s power supplies and basically everything Ham Related, most of the stuff went straight to the tip, but a few items that semi-survived that had just a small showering as opposed to a deluge of water being dumped upon them, were put into the airing cupboard and forgotten until now, one of the rare candidate’s to look at was this Ten-Tec, I opened her up and gave her a quick look over and was really surprised that there seemed to be little damage from the water at all even though I do remember having to leave her at the time over a bucket draining water at the time.
The number of times that I have taken a Jet Washer to a chassis of an old Vacuum Tube radio knowing that this is sometimes the best way to clean up years of grime, but I would drown a Radio that has IC’s and Transistors inside of it, that is a complete no no.
Anyway, it had not been attached to a power supply since 2014 and after a few tests I bit the bullet and switched it on, surprisingly it switched on and I even managed to start tuning into a few signals, but after about 5 minutes there was a loud bang and the radio reset, it seemed to work alright up until it reset itself.
I am hoping that this is to do with a well-documented issue with these old Ten-Tecs in that the three main capacitors on the ‘A9 Power Distribution Board’ would need to be replaced with something a little beefier, so I ordered some good quality Capacitors for this task in the hope that this would sort this issue out.
With the Top Case removed we can see the following sections and the modules that are installed:
A1 – The Low Pass Filter
A6 – Sub Receiver
A4 – IF
A5 – IF Converter (Under the Speaker)
Whilst we are looking at this side of the unit we might as well check out what filters are installed in the Orion I, you just need to remove the screw from the plate above the filters so that we can see the actual filters that are installed.
In my case it is very ‘Standard’, I have the 6KHz, the 2.4KHz and the 1KHz, so somehow I need to find the missing ones, the 1.8KHz, and possibly higher on my wish list are the two narrow filters, the 500Hz and the 250HZ filters, this is going to be a big challenge, especially with Ten-Tec basically being dead now, albeit by name alone.
But turning the radio over to see the side that we are more interested in, The Bottom View lets us see the following Modules:
A3 – RF Converter
A14 – Automatic Antenna Tuner (Missing in Mine)
A10 – Synthesizer
A9 – Power Distribution
We want to look at is the small A9 Power Distribution Board
One thing about these Ten-Tec’s and their Modular Builds is that they are very easy to get to what you are after, in our case it’s this very small board on the bottom right of the bottom side of the radio.
To remove the A9 Power Distribution board all you need to do is remove 4 screws and then unplug the white plug with the two white leads.
Just be a little careful, under each of the screws is small clear plastic washer/gromit, be careful not to lose these, they can easily fall out or you may find them attached to the screw when you remove them, they are a bit unique and could be a little hard to find a replacement, I am only mentioning this because I lost one on the floor and it took ages to find, Opps.
We are interest in the three large Electrolytic Capacitors, these are all 470mF and rated at 16v, these need to be replaced by ‘Good Quality’ and NOT Cheap, 50v replacements.
It is recommended that you mark the PCB so that you do not get the replacement capacitors the wrong way round, well worth doing as the new capacitors are slightly wider than the original ones.
I had a real problem finding quality capacitors in the UK, I was amazed at just how difficult this was, getting stock from any of our regular suppliers, I tried Farnell, CPC, Mouser, DigiKey and a few small suppliers as well, in the end I had to order some from the USA which would obviously slow down the repair of this radio, so yet another box gets put on the shelf to join everything else, this is what annoys me somewhat and why restorations take so long, and being on an island in the middle of the Irish sea adds yet more time to these restorations, especially of older units which are waiting on people to offer parts on ebay.
Above I have highlighted the 3 capacitor connection on the underside of the A9 Distribution board.
I had a bit of an issue de-soldering the Capacitor from the board, and I could not clean the solder up either, I am not sure if it was not leaded solder, but it would not suck up at all, and I tried de-solder braid as well.
In the end I just ran a small drill through the holes with a Dremel.
When I flipped the board over I noted that it looks as though the 2 transistors had also been replaced at some point, the soldering was a bit duff here.
I tested each Capacitor as I removed them and they all seemed to be alright, and surprisingly quite a lot better than the new capacitors which although within tolerance, they were not as good as the original ones.
Well, that is one done and cleaned up, I was a little worried about just how difficult this was to solder, it is strange stuff, hopefully I will not have as much trouble with the final two.
This was not my proudest moment, a mix of bad solder, too smaller pads, and for some reason I was unable to clear the holes, in the end all of the holes had to be drilled out, I tried my best flux, various irons and de-soldering stations and for some reason this was a real pain in the but, after a good clean I managed to get the solder to take, but I was no happy with this one, it was clean and as I will find it works, but you know when you feel that it should have been better than it was.
When placing the A9 board back into the chassis, you will need to make sure that all 4 screws have the clear washer installed as shown here.
With the bpard placed back in the chassis I connected up the power to check that all was alright, after leaving it switched on for an hour I can only say that there was no loud ‘crack’ or a reset and reboot of the power, so all is well so far, fingers crossed.
The Next Project
I still would like to replace the screen on this radio as it is starting to loose it’s contrast, this is not a simple replacement though, but I feel it is worth doing, the radio itself is still a good radio and I is still feel that it is very capable even if it is a tad old, but as I cannot afford a Yaesu FTDX-5000 or a FTDX-10 I feel that this radio is still as good these days.
Initial Release – Firmware Version 1.325
26th March 2003 – Firmware Version 1.326
- Fixed DV memory record/recall feature. Flash write & Recall was intermittent.
- Added STOP action to SEND1,2,3 buttons.
- PTT now ignored during voice record to prevent audio pop being recorded.
27th March 2003 – Firmware Version 1.327
- TX Meter hang increased from 200 mS to 300 mS
28th March 2003 – Firmware Version 1.328
- Pre-amp display now updated after a master reset.
- Expanded band edges by 10 kHz to cover some MARS frequencies.
31st March 2003 – Firmware Version 1.329
- Changed vox routine. Was not restoring correct vox gain after a power cycle.
- Fixed DSP Audio selection conflict between Bin Rx and phones selections.
- Master Reset state of Binaural Receive changed to OFF.
1st April 2003 – Firmware Version 1.330
- Improved Audio Menu MULTI routine.
- Reduced size of Sub receiver S-Meter to prevent overwrites of the Audio Menu.
2nd April 2003 – Firmware Version 1.331
- Fixed bug that caused TX to be disabled when tuner went into Bypass State.
- Added code to restore RX and TX Equalization values after power-cycle.
3rd April 2003 – Firmware Version 1.332
- Fixed audio menu bug that caused MULTI to adjust values in only one direction.
- Binaural RX state now restored at power up.
- Fixed bug on preset antenna selections.
- RX ANT LED update added to recall of antenna presets.
- Fixed bug in VOX system that caused the radio to key when vox first tuned on.
4th April 2003 – Firmware Version 1.333
- Fixed FAST/SLOW encoder. FAST was tuning two times steps.
6th April 2003 – Firmware Version 1.334
- Fixed bug in Keyer paddle routine that caused loss of rx at power-up when grounded.
- Continued revision/testing of serial interface.
- New DSP code v151 to fix distorted speech monitor in AM Transmit.
7th April 2003 – Firmware Version 1.335
- Fixed another bug in the Audio Menu BinRx routine. Failed to re-program the sub-dsp’s audio selections when BinRx went to OFF.
8th April 2003 – Firmware Version 1.336
- Changed rollover of EQ settings in audio menu to +/- limits of 20.
10th April 2003 – Firmware Version 1.337
- Now clearing multi-encoder after moving highlight in the menu screens.
- Now rounding/truncating Vfo frequencies based on selected step.
- Changed Master Reset value of VFO-B to 14.035 LCW.
- Added Step-Multiplier function to [MAIN RX] and [SUB RX] buttons.
11th April 2003 – Firmware Version 1.338
- Modified FM operation.
- Extensive work on the serial interface.
14th April 2003 to 16th April 2003 – Firmware Version 1.339
- Fixed bug in M->VFOB that caused VFOA freq to appear in VFOB display area and cover-up VFOB value.
- Changed Freq rounding routine to make single step after step side change. Was making two steps when moving down.
- Fixed NR and AN multi-enc behavior that caused them to occasionally turn off when being turned!
- Lots,lots,lots of work on the serial interface!
26th April 2003 to 6th May 2003 – Firmware Version 1.340
- DSP modified correct sub receiver QSK audio pops.
- Corrected Sub receiver RIT Operation.
- Final Serial Interface Updates. Release with Programmer’s Ref Guide.
3rd June 2003 – Firmware Version 1.344
- Modified tuning/BFO routines to improve crystal filter placement in CW modes.
6th June 2003 – Firmware Version 1.345
- TUNE now stops automatically when the tuner is finished.
- Key line/Paddles now stops CW playback.
- Eliminated garbage character beside display of sidetone pitch in CW MENU.
- Fixed Linker problem that caused garbage to appear in MEM window background.
13th June 2003 – Firmware Version 1.347
- Added trap for 60M band data to handle Flash update without Master Reset.
- Modified Serial Initialization routine to stop buffer clear on power-up/reset.
25th June 2003 – Firmware Version 1.348
- Added POD routing control to allow pod actions to be sent to a host PC.
- Corrected reporting of squelch query value.
- Corrected screen updates of AGC and Attn when changed via the serial port.
- Corrected muting on voice-playback, did appear to stick in Tx after playing.
- Added Filter-Associated Automatic Threshold adjustment to the AGC system.
- Added Filter Reset Option to the reset sequence.
10th July 2003 – Firmware Version 1.350
- Added code to force QSK delay to 0 in when using the tune function.
- Increased PBT ranges to 2500 Hz.
- Implemented corrections to FSK mode and enabled FSK input on rear panel.
- Changed Notch defaults to 300Hz wide at 1000 Hz center freq.
29th July 2003 – Firmware Version 1.351
- Sub receivers now connected to VFOB on master-reset.
- Added FSK monitor function.
- Now updating band-data when VFO changes.
- Added forced update to PBT/BW controls when Tracking changed in the menu.
- Fixed bug in Memory recall. Was not correctly storing the BW in the memory.
- Added keyer lockout so it can be used only in the CW modes.
- Added Xtal Filter Gain correction and correction for DSP bandwidths <150 Hz.
- Added S-Meter correction as part of the change above.
- Added Super-programmable AGC features.
7th August 2003 – Firmware Version 1.352
- Changed PTT routines to use timed key-down measurements and programmed delays.
- Changed amp-loop routine to operate with the new key routines.
11th August 2003 – Firmware Version 1.353
- Fixed SUB/MAIN RIT display subroutine so they were updated when RIT was on.
- Reworked PBT/BW TRACKING routines to eliminate the odd behavior.
12th August 2003 – Firmware Version 1.354
- Completely turned OFF the CW key input is SSB Mode.
- Eliminated erroneous display of Hz at the end of the CW_MENU.
- Added Mode, BW and PBT to A-B & B-A exchanges.
- Dependent on Tracking Settings.
- Added calls to clear ‘tuned’ word from display after disengaging the tuner from the TX menu.
- Modified SWEEP clear functions to clear up junk on the screen when turned OFF.
- Modified VRP system because the DSP was staying in transmit after playback.
- Added code to clear the Voice and CW recorders indicators in FSK mode.
15th August 2003 – Firmware Version 1.355
- Reorganized the new BBRAM values to eliminate the need for a master-reset between 1.349 and 1.355.
- Fixed pointer bug that caused pod to misbehave when the FSK was inverted.
- Fixed erroneous dot left on the display after transmit.
- Fixed SP bug that caused it to be ON at power-up even though it was OFF.
- Realigned the sub-receiver mode indicator in the display.
- Changed labeling for OTHER_MENU item selecting FSK TX Data Sense.
- Changed the sub-meter drawing routine to prevent overwriting AUDIO MENU.
19th August 2003 – Firmware Version 1.356
- Modified serial interface AGC set routines to account for the new super-programmable AGC controls.
- Modified VRPB key-down routines to integrate new timed key-down routines.
- Removed rollover from the FSK menu option.
21st August 2003 – Firmware Version 1.357
- Added CW MENU selection to enable CW Key to be PTT in SSB modes.
- Fixed CW Playback bug that caused stuck key-down in CW mode.
- Modified NB Display routine to properly clear the ‘H’ indicator when Hardware NB tuned OFF in menu.
- Fixed line segment missing after a band change. (Between MON and SP functions)
25th August 2003 – Firmware Version 1.359
- Added Hardware NB control to the NB button. Press and Hold to toggle.
- Added bandwidth/mode association. Mode auto recalls last used BW.
- Corrected drawing in mode menu to remove Unwanted lines on left of screen.
- Modified sub receivers AGC hang setting serial port function.
12th September 2003 – Firmware Version 1.360
- Added cross-mode ability via VFO selection.
- Added restore of mode/bw association to the serial port mode set command.
16th September 2003 – Firmware Version 1.361
- Keyer Speed and SEND selections now change based on the transmit mode. (part of the cross-mode changes)
- Changed TUNE mode to take into account the new cross-mode tx capability.
- Added BW and PBT exchange to the A/B swap function.
25th September 2003 – Firmware Version 1.362
- Corrected SUB RX FSK PBT bug. Was jumping to 0 when the PBT was adjusted.
- Added calls to update BW values on display when recalling a band registers.
- More patches for voice record/cross mode operation.
- Modified serial interface TUNE routine to fix hang-up.
- Added lock-out to TUNE BUTTON if the radio is already in transmit.
- Modified NB/NR DSP for improved handling of large signals.
Firmware Version 1.368 (Not Released)
- Expanded 60M band to 5.425 to include Norways 5.410 and 5.420 allocations.
- Modified tuning code to reduce the tuning stutter at high encoder rotations.
- Fixed Menu item placement in FILTR, VOX and SSB Menus.
- Added the remote pod encoder control back to the VFO controls. Needed because of tuning changes.
Firmware Version 1.373b1
- Added additional checks for Curtis keyer control to MENUs. Was only called on power-up.
- Add WAIT_FOR_DSP_COMPLETE to mainRF routine. Toby P was reporting noise bursts.
- Added call to agc_change in serial AGC routine.
Firmware Version 1.373b2
- Removed call to update xtal filter drivers inside the PBT_BW routine. This is now handled in the interrupt routine. Having it in two placed was causing a conflict when writing to the interface chips.
- Added main_dsp_squelch variable to handle MOX for the main receiver. Was inadvertently using the sub receivers squelch value for the mains MOX unmute value. This caused a SQL problem when the main receiver was in CW mode anytime.
Firmware Version 1.373b4
- Eliminated passing of AGC info to DSP. This was causing Out of Band distortion when used.
Firmware Version 2.058
- Modified the AGC system. Now has slow attack to eliminate hang-up on news spikes.
- Modified the Speech Processor to use envelope detection for gain changes instead of peak-detection.
- Relocated the NR and NOTCH functions down one decimation level to reduce the processor load!
- Fixed scaling inside manual notch function that caused numeric overload.
Firmware Version 2.060a
- Increased AM Rx BW to 9KHz.
- Added soft limiter to FM Transmitter.
- Added on screen BAND REGISTER indicator.
- Added on screen SPLIT indicator.
- Improved AM TX carrier level.
- Improved QSK.
Last Updated : 5th November 2023