From: ka2raf@nn2z.nj.usa.na To: 850mod@allbbs Subject: TS850S mods 1 Having lived with Kenwood's TS-850S tranceiver for 5 days, here are some of my observations: . While the manual shows 35 power-on front panel adjustments, there really are 36. Function number 35 is set from the factory to the OFF state. Well, what exactly is this unknown function? Well Bunkies, this enables the tranceiver to transmit on 27.500 through 28.000 mhz! Do yourself a favor, and set this option to ON for TX inhibit! DO NOT JEAPORDIZE YOUR LICENSE! Why in the world did the factory allow this??? Maybe they don't want the Chicken Banders butchering up the rigs.... . Tone control. The setup only allows Burst or Continuous modes, there is no way to turn it OFF, even though the manual indicates there is a way. . Quick memory function. You MUST pass through either the VFO A or VFO B registers to program these.. You cannot go from standard memory to quick memory directly. . My 850S came out of the box running low power (50 - 75w PEP), so I called the local ham radio dealer inquiring about service manual availability. Well they had them in stock, but at a price of $50.00! Unbelievable! Kenwood wants fifty dollars for (in the continuing Kenwood tradition) a terribly organized, incomplete, and horrible reading manual!!! Well, I dug into the schematics and opened up the the radio, here's a list of items that might be of interest to some: RF Board Controls ----------------- VR - RX BAL VR - TX BIAS VR - TX BAL VR - TYP (50W output power adjust, used with S1 below) VR - MIN (?????) / internal antenna tuner VR - TUN (Tune mode power adjust) VR - VSF (THIS IS THE 100W POWER OUTPUT CONTROL) VR - SWR Protect activation VR - PWM (Forward power meter calibration) VR1 - RWM (Reflected power meter calibration) VR1 - AL0 (ALC meter zero) VR1 - ALM (ALC meter calibration) VR1 - CPM (Processor meter calibration) VR1 - ALG (ALC gain adjustment) S - All Band Power Down Switch (Decreases power to 50 watts) IF Board Controls ----------------- VR - VR - VR - VR - Beep volume VR - Sidetone volume VR - Processor adjust VR - ????? VR8 & VR9 - ????? VR1 - ????? VR1 - VR12 & VR13 - S Meter adjust VR14 & VR15 - AGC adjust VR1 - Notch filter adjust . PLEASE NOTE! Most of these controls are 1/8" pots, so if you intend to adjust them use a VERY SMALL non-metallic tool. . My 850S also came out of the box with the RIT/XIT control not dis- playing 0.00 khz at fiducial (12 o'clock position) center. Behind the front panel in the upper right corner is the control for center adjust. It just needed a wee bit of tweaking... Along with this control on the circuit board are the master adjust- ments for the SSB slope tuning (High Cut and Low Cut). . When both top and bottom covers are removed, on the left-hand side is the FM board. There are 3 (three) pots on the board. They are FM Wide (12khz) deviation, FM Narrow (6khz) deviation, and FM Mic gain. Author's note: I cannot say whether ALL the information above is accurate. I do not purport to be an electronics wizard, but am just an Amateur radio operator who wants to get the most enjoyment out of his equipment Let's beat the ridiculous cost of poorly written service manuals! Add to this document and please circulate it! 73, Jan - KC2CT Subject: TS850S mods 2 More Observations As Of 6-26-91 - KC2CT --------------------------------------- . FM mode defaults to WIDE (12khz). This is WAY too wide for accessing any 10m repeater. Hit the 455khz filter button again for FM-N (narrow). This will set the IF to 6khz width, and you be able to work FM 10m stations. Note: The 8.83 filters are NOT selectable in FM mode. . Memory scrolling via M CH./VFO CH. You can bypass all unused channels if you press the 1 mhz button. With the button active, only stored memory channels will be displayed as the knob is rotated. . Tuneable memories. Out of the box, the radio is set up for non- tuneable memories. Just bring up setup function xx on the display, and set it to ON, and ALL memories can be tuned via the VFO. When use the M.CH/VFO CH. switch you will be returned to the original frequency & mode setting in the memory. . It may or may not be obvious to some, but the radio is capable of cross-band and/or cross-mode operation. Just pump the required modes and frequencies into memory channels or VFOs, and you're off and running. Hope you have a very broadbanded antenna! . CW message storage is lost when you power off the radio. I didn't order the DRU-2 option (yet), so I don't know whether these messages will be saved. You'd think that with everything else that is stored in RAM and backed up by battery, that Kenwood would have made pro- visions to keep recorded messages alive also. A modification???? . When adding additional filters, is is necessary to set the corresponding switch on. Under the hatch on top, is a 4 position dip switch. The manual shows a picture of it, but makes no mention of their settings. This switch is necessary to inform the micro- processor of the filters' absence or presence. ON is for presence, OFF is for absence. Below is the switch diagram: ----- | = | <-- YK-88C-1, YK-88CN-1, YK-88SN-1 | = | <-- YK-88CN-1, YK-88CN-1, YK-88SN-1 | = | <-- No Function | = | <-- YG-455C-1 or YG-455CN-1 ----- O O N F F Subject: TS850S mods 3 More Observations As Of 6-30-91 - KC2CT --------------------------------------- Well here I am again with more stuff on the 850S... . I received the DRU-2, voice recording unit this week, and installed it.Here's what I found: . The unit comes with a lithium battery for backing up the voice messages when the rig is powered off. . The initial state of the DRU-2 is: Message 1 - 8 seconds Message 2 - 8 seconds Message 3 - 16 seconds You can halve the sampling rate via front panel setup control xx. This will effectively DOUBLE the time of of each message, however, the quality of voice repro- duction will suffer because of the lower sampling rate. . On playback of the messages, the microphone IS NOT disabled, so be quiet when you're transmitting stored messages. . Use the MONI function to hear what you've recorded and/or are transmitting, and the MIC gain control to keep the ALC in range, as the DRU-2 drives the radio much harder than the microphone input. . The high boost function and speech processor are available to the DRU-2 during transmit. . I also got the VS-2 voice unit. The voice is the same as the older VS-1 for the TS-440, and TS-940, but the unit is in a smaller package. It will speak the frequency in either English or Japanese. There is a volume control pot on the bottom of the board which should be adjusted PRIOR to screwing down the VS-2. The output on my unit was very low, until I tweaked it up. Also there are jumpers on the board to speed up the voice playback... You'll need to consult the instruction page for the VS-1 for speeds, as there is nothing mentioned in the instructions for the VS-2. . A note on output power of the rig. The radio uses 2SC2789's... These devices are rated as 100 watt devices Kenwood is running the finals VERY conservatively. When playing around with output, I had the rig dead-keying 175 watts, but backed it down to 100 watts, as I didn't want to blow up the rig, but I was definitely smiling as the Birds' meter swung with a 250 watt slug! . The ROM chip on the digital board is socketed. Kenwood had problems with early 440's and 940's with poor soldered connections. While it's a nice idea to allow removal and replacement of the ROM to add features/fix bugs, this might become a problem area in the future. . Hidden function!!! If you turn on the radio while holding down the VOICE button, EVERY button on the radio will acknowledge its function via morse code! This is a terrific feature for sightless hams! I can't understand why it is not mentioned in the owners manual or marketing literature! Subject: TS850S mods 4 Still MORE Observations - KC2CT - 07-05-91 ------------------------------------------ Well if you've been following this brief series, you probably know by now, that despite any criticism, I really LOVE my 850S! I've really dug into the guts of the radio, and truly find it a pleasure to explore and operate..Well here's a few other items that should be of interest to other hams: . ALL BAND TRANSMIT ----------------- Kenwood markets this radio worldwide, and has made provisions to allow the radio to transmit between 1.625 mhz and 29.999 mhz. I am providing this modification for INFORMATIONAL PURPOSES ONLY! DO NOT TRANSMIT OUT OF BAND, THIS WILL JEAPORDIZE YOUR LICENSE, AND HAVE THE FCC, AND/OR INTERNATIONAL AUTHORITIES KNOCKING AT YOUR DOOR!!! The All-band transmit modification requires the removal and re- location of a diode on the the digital board which is located behind the front panel. The US version of the radio has diode D11 installed, and diode D9 removed. D11 must be removed, and installed in the D9 position. This modification IS NOT for the faint of heart, as it entails removing the front panel, and the digital board. Note that the digital board has solder holes that are through-soldered; that is, there are circuit traces on both sides of the board, so make sure that ALL solder is removed from the holes. This modification will also allow the antenna tuner to tune anywhere the receiver is tuned. This modification should ONLY be performed by those familiar with soldering and de-soldering techniques, and requires patience, and dexterity. . Broadcast Band Sensitivity -------------------------- BCB sensitivity REALLY suffers as a 24db attenuator is inserted when band-switched. This attenuator circuit is very similiar to the TS-430/440. Possible modification? . Additional Front Panel Functions -------------------------------- Pressing SCAN + TX-M.CH will set the radio into its extended function mode. These options can be scrolled via the M.CH/VFO CH. switch. The following are the extended functions: 00 - This is the ROM Checksum displayed as a 4-digit hexadecimal number This cannot be changed. 01 - Allow filter selection in transmit. Initially set OFF. 02 - Antenna tuner power down. Initially set to OFF. 03 - Antenna tuner non-stop mode. When set to on, the antenna tuner will not stop when the lowest VSWR is found. Initially set to OFF. 04 - Store mode, and filter settings prior to changing bands, or channels. Initially set to ON. 05 - Display -HELLO- on digitial display, and send it in Morse code on power up. Initially set OFF. 06 - Turn full LCD display ON on power on. Initially set OFF. 07 - Turn Subtone ON or OFF. Initially set ON. Note that even when set off, the TONE indicator will be lit on the display. 08 - Unknown. Initially set OFF. ------------------------------------------------------------------------