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I'm going to write an FT-980 driver for flrig.

This will allow GUI control of tuning, IF? Shift and the other "locked out" functions. As Wald pointed out, for FT-8 (or any of the modes supported by wsjt-x, for that matter) the program automagically does most of what's needed. fldigi can use flrig as its tuning mechanism, and while not the same as spinning a VFO dial I've used this setup to tune my IC-751A/R-71A across the bands while operating digital modes. The '980 command set should add a little functionality over the Icoms of the same era.

Pie-in-the-sky would be concurrent dual radio support via flrig. Maybe hit a "sync" button and the transceiver follows a connected receiver, which could be used for tuning around the bands in search of interesting things. Or the transceiver always follows if a continual sync option is selected. I've a somewhat lengthy list of rig drivers to write for that application, and among them is one for the NRD-535D - which I'll probably use as a spotting RX for the FT-980.?

Stuff to ponder. It's all ones and zeros anyway.

73 - Fred, N8YX

I played around with hamlib for a bit, submitted a change, even started work to improve the interface.

The biggest issue with the FT-980 I found is that most of the front panel interface locks out when you enter CAT, and CAT changes are temporary (ephemeral).?


--
-Mat Breton, N8TW

Dear all,

I asked a question to the Hamlib mailing list and got the following
reply:



It turned out that if I pass "-C dtr_state=ON" option to rigctl, it
works fine without timeouts.

Thanks for the information on FT8 and logging programs. It is good to
know that I can use FT-980 for FT8. I am new to FT8, but would like
to try it in the near future. I am now finding how to do the audio
interface. I think I should connect AF OUT in the back panel of
FT-980 to the computer's Line In and PATCH IN to the Line Out. Am I
right?

--
Kenichi Asai

All,

I've been doing a bit of rig driver development for flrig over the last few months.

Absent from its list of supported radios is the FT-980. As soon as I finish the Optoelectronics scanner driver (Optocom, OS-535, etc.) I'll fix this omission. WSJT-X can use either hamlib or flrig as its radio-control front end, as can fldigi. Both support logging of one form or another.

73 - Fred, N8YX

Thanks JMat for various information! I made similar observation on
the log. After that, I looked into the source code of Hamlib library
and found that if I replace the line:



from:

result = port_select(p, fd + 1, &rfds, NULL, &efds, &tv, 1);

to:

result = port_select(p, fd + 1, &rfds, NULL, &efds, NULL, 1);

and recompile rigctl, I could successfully communicate with FT-980S
with "rigctl -m 1031 -r /dev/tty.usbserial-10"! Since the port_select
function eventually expands to select function, the change effectively
removes the timeout of select. However, even if I set the timeout
long enough by passing "-C timeout=10000" option to rigctl, the
original rigctl times out. I don't know why.

I am still interested in if anybody could talk to FT-980 from linux or
windows. It would then mean that the select function of mac does not
behave as we expect. Otherwise, I would consider asking a question to
the Hamlib mailing list.

Yes, locking during CAT control is annoying. The communication speed
would also be a problem. But FT-980S is my favorite rig I have been
using for 40 years, and I would like to explore its possibilities some
more.

--
Kenichi Asai

Hello?Kenichi,

I'm not an expert un CAT for FT-980, but in the past I tried using Omnirig and Omirig Client.
The details of CAT protocol are given in page 13 (page 15 of PDF) in service manual :
http://www.radiomanual.info/schemi/YAESU_HF/FT-980_serv.pdf

The physical link is in TTL (not in RS232), or without line transciver that invert the signal.
Normaly the FT-980 send a echo of the command in half duplex (see figure on bottom of page 13)
Using an oscilloscope you must see it? on Rx pin !

Based on your log, you send "Extrl crtl on/off" command :
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00

then the read command should recieved the same :
...and here nothing is recieved !
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4995 seconds after 0 chars, direct=1
If the FT-980 recieve correctly this command the front panel is locked during CAT control !

Personnaly I gave up this transciver in CAT mode because all of digital controls are locked on front panel during CAT control !
It could be used in remote, but analog controls are not possible in CAT !?
And the response in CAT mode is really slow :? to get the frequency a STATUS CHECK is 148 bytes to read !!!

The FT-980 was one of the first in CAT mode, but the controller (CPU 8085) is really limited !
It is an 8-bit microprocessor designed by Intel in 1977 ! ! !

Regards,
JMat (Jean-Matthieu)
73 de F5RCT

I am fascinated to find a thread in this FT-980 group to discuss CAT
connection to FT-980 using Hamlib library. I am now trying to do it
myself. However, when I try to use rigctl in the Hamlib library, it
times out. Since I could connect to and get information from my
FT-980S using a simple program that I wrote, I think hardware
connection is OK. My question is:

(1) Could any of you connect using rigctl to FT-980?

(2) If yes, what options did you use? I used:

rigctl -m 1031 -r /dev/tty.usbserial-10 -vvvvv

but it times out. I include the log below. What am I doing
wrong?

I am using Hamlib 4.5.2 installed via homebrew on M1 mac (Big Sur).
Any help/information is appreciated! Thank you in advance.

--
Kenichi Asai


$ rigctl -m 1031 -r /dev/tty.usbserial-10 -vvvvv
rigctl.c(445) Startup: rigctl -m 1031 -r /dev/tty.usbserial-10 -vvvvv
rigctl Hamlib 4.5.2 Fri Dec 23 23:04:12 2022 +0000 SHA=f12ac6
Report bugs to <hamlib-developer@...>

rig_check_rig_caps: p1=0x100f02d20, p2=0x100f092a0, rig_model=0x100f02d20, macro_name=0x100f092a0
yaesu: initrigs4_yaesu called
rig_init: rig_model=Yaesu FT-980
rig_init: backend for FT-980 does not contain hamlib_check_rig_caps
rig_init: rig has VFO_SUB
rig_init: rig has VFO_MAIN
rig_init: rig has VFO_MEM
ft980_init called
1:rig.c(812):rig_open entered
rig_settings_get_path: path=/Users/asai/.config/hamlib_settings
rig_settings_load_all: settings_file (/Users/asai/.config/hamlib_settings): No such file or directory
rig_open: cwd=/Users/asai
rig_open: /Users/asai/hamlib_settings does not exist
rig_open: async_data_enable=0, async_data_supported=0
serial_open: /dev/tty.usbserial-10
ser_set_rts: RTS=0
ser_set_dtr: DTR=0
serial_setup: tcgetattr
serial_setup: cfmakeraw
serial_setup: cfsetispeed=4800,0x12c0
serial_setup: cfsetospeed=4800,0x12c0
serial_setup: data_bits=8
serial_setup: parity=0
serial_setup: Handshake=None
serial_setup: tcsetattr TCSANOW
read_string_generic called, rxmax=4095 direct=1, expected_len=1
ser_set_rts: RTS=0
2:rig.c(7417):async_data_handler_start entered
async_data_handler_start: async data support disabled since async_data_enabled=0
2:rig.c(7424):async_data_handler_start returning(0)
rig.c(254):add_opened_rig returning2(0)
rig_open: 0x13600ce1c rs->comm_state==1?=1
ft980_open called
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5024 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5034 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 0b .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5054 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5005 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5036 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 0b .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4996 seconds after 0 chars, direct=1
rig.c(1275) trace
2:rig.c(2879):rig_get_vfo entered
rig_get_vfo: cache check age=1000000ms
rig_get_vfo: cache miss age=1000000ms
rig.c(2921) trace
ft980_get_vfo called
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5003 seconds after 0 chars, direct=1
rig_get_vfo: returning -5(read_block_generic called, direct=1
read_block_generic(): Timed out 2.4996 seconds after 0 chars, direct=1
rig.c(1275) trace
2:rig.c(2879):rig_get_vfo entered
rig_get_vfo: cache check age=1000000ms
rig_get_vfo: cache miss age=1000000ms
rig.c(2921) trace
ft980_get_vfo called
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5003 seconds after 0 chars, direct=1
Communication timed out
Communication timed out
)
2:rig_get_vfo: elapsed=2435ms
2:rig.c(2942):rig_get_vfo returning(-5) Communication timed out

rig_open: vfo_curr=currVFO, tx_vfo=TX
rig_open: default vfo = currVFO
rig_get_freq(1985) called vfo=VFOA
vfo_fixup:(from rig_get_freq:1991) vfo=VFOA, vfo_curr=currVFO, split=0
rig.c(1994) vfo=Main, curr_vfo=currVFO
rig_get_freq: cache miss age=1000000ms, cached_vfo=Main, asked_vfo=Main, use_cached_freq=0
rig_get_freq(2081): vfo_opt=0, model=1031
ft980_get_freq: called
ft980_get_freq: passed vfo = 0x4000000
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4996 seconds after 0 chars, direct=1
1:rig_get_freq: elapsed=2436ms
1:rig.c(1370):rig_open returning(0)
Opened rig model 1031, 'FT-980'
Backend version: 20200114.0, Status: Stable
rigctl_parse: called, interactive=1

Rig command: m
rigctl_parse: input_line: m
rigctl_parse: vfo_opt=0
1:rigctl_parse.c(2237):rigctl_get_mode entered
2:rig.c(2404):rig_get_mode entered
vfo_fixup:(from rig_get_mode:2427) vfo=currVFO, vfo_curr=currVFO, split=0
vfo_fixup: Leaving currVFO alone
rig_get_mode: currVFO cache check age=8325ms
rig_get_mode: cache miss age mode=8325ms, width=8325ms
rig.c(2475) trace
ft980_get_mode: called
ft980_get_mode: passed vfo = 0x20000000
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5063 seconds after 0 chars, direct=1
rig_get_mode: retcode after get_mode=-5
3:cache.c(35):rig_set_cache_mode entered
3:cache.c(108):rig_set_cache_mode returning(0)
2:rig_get_mode: elapsed=2432ms
2:rig.c(2537):rig_get_mode returning(-5) Communication timed out

1:rigctl_parse.c(2243):rigctl_get_mode returning(-5) Communication timed out

get_mode: error = 0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5063 seconds after 0 chars, direct=1
rig_get_mode: retcode after get_mode=-5
rig_get_mode(2479): freqMainA=0, modeMainA=, widthMainA=0
rig_get_mode(2479): freqMainB=0, modeMainB=, widthMainB=0
3:cache.c(35):rig_set_cache_mode entered
rig_set_cache_mode(37): freqMainA=0, modeMainA=, widthMainA=0
rig_set_cache_mode(37): freqMainB=0, modeMainB=, widthMainB=0
rig_set_cache_mode(107): freqMainA=0, modeMainA=, widthMainA=0
rig_set_cache_mode(107): freqMainB=0, modeMainB=, widthMainB=0
3:cache.c(108):rig_set_cache_mode returning(0)
rig_get_mode(2534): freqMainA=0, modeMainA=, widthMainA=0
rig_get_mode(2534): freqMainB=0, modeMainB=, widthMainB=0
2:rig_get_mode: elapsed=2432ms
2:rig.c(2537):rig_get_mode returning(-5) Communication timed out

1:rigctl_parse.c(2243):rigctl_get_mode returning(-5) Communication timed out

Communication timed out

main: i/o error
1:rig.c(1392):rig_close entered
ft980_close called
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4213 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5015 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5049 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4994 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 0b .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.1516 seconds after 0 chars, direct=1
2:rig.c(7461):async_data_handler_stop entered
2:rig.c(7491):async_data_handler_stop returning(0)
ser_set_rts: RTS=0
ser_close: restoring options
rig_close(1528): 0x13600ce1c rs->comm_state==0?=0
1:rig.c(1530):rig_close returning(0)
main: rig_close retcode=0
1:rig.c(812):rig_open entered
rig_settings_get_path: path=/Users/asai/.config/hamlib_settings
rig_settings_load_all: settings_file (/Users/asai/.config/hamlib_settings): No such file or directory
rig_open: cwd=/Users/asai
rig_open: /Users/asai/hamlib_settings does not exist
rig_open: async_data_enable=0, async_data_supported=0
serial_open: /dev/tty.usbserial-10
ser_set_rts: RTS=0
ser_set_dtr: DTR=0
serial_setup: tcgetattr
serial_setup: cfmakeraw
serial_setup: cfsetispeed=4800,0x12c0
serial_setup: cfsetospeed=4800,0x12c0
serial_setup: data_bits=8
serial_setup: parity=0
serial_setup: Handshake=None
serial_setup: tcsetattr TCSANOW
read_string_generic called, rxmax=4095 direct=1, expected_len=1
ser_set_rts: RTS=0
2:rig.c(7417):async_data_handler_start entered
async_data_handler_start: async data support disabled since async_data_enabled=0
2:rig.c(7424):async_data_handler_start returning(0)
rig.c(254):add_opened_rig returning2(0)
rig_open: 0x13600ce1c rs->comm_state==1?=1
ft980_open called
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5060 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.1723 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 0b .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.3258 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.2817 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5007 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 0b .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.3508 seconds after 0 chars, direct=1
rig.c(1275) trace
2:rig.c(2879):rig_get_vfo entered
rig_get_vfo: cache check age=48629ms
rig_get_vfo: cache miss age=48629ms
rig.c(2921) trace
ft980_get_vfo called
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4997 seconds after 0 chars, direct=1
rig_get_vfo: returning -5(read_block_generic called, direct=1
read_block_generic(): Timed out 2.3508 seconds after 0 chars, direct=1
rig.c(1275) trace
2:rig.c(2879):rig_get_vfo entered
rig_get_vfo: cache check age=48629ms
rig_get_vfo: cache miss age=48629ms
rig.c(2921) trace
ft980_get_vfo called
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4997 seconds after 0 chars, direct=1
Communication timed out
Communication timed out
)
2:rig_get_vfo: elapsed=2438ms
2:rig.c(2942):rig_get_vfo returning(-5) Communication timed out

rig_open: vfo_curr=currVFO, tx_vfo=TX
rig_open: default vfo = currVFO
rig_get_freq(1985) called vfo=VFOA
vfo_fixup:(from rig_get_freq:1991) vfo=VFOA, vfo_curr=currVFO, split=0
rig.c(1994) vfo=Main, curr_vfo=currVFO
rig_get_freq: cache miss age=48630ms, cached_vfo=Main, asked_vfo=Main, use_cached_freq=0
rig_get_freq(2081): vfo_opt=0, model=1031
ft980_get_freq: called
ft980_get_freq: passed vfo = 0x4000000
ft980_get_status_data called
rig_check_cache_timeout called
rig_check_cache_timeout: forced cache timeout
ft980_transaction called
rig_flush: called for serial device
read_string_generic called, rxmax=4095 direct=1, expected_len=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 01 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.3665 seconds after 0 chars, direct=1
1:rig_get_freq: elapsed=2431ms
1:rig.c(1370):rig_open returning(0)
main: rig_open retcode=0
rigctl_parse: called, interactive=1

Rig command: q
1:rig.c(1392):rig_close entered
ft980_close called
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5002 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.5040 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4503 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 00 .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4999 seconds after 0 chars, direct=1
write_block(): TX 5 bytes, method=1
0000 00 00 00 00 0b .....
read_block_generic called, direct=1
read_block_generic(): Timed out 2.4995 seconds after 0 chars, direct=1
2:rig.c(7461):async_data_handler_stop entered
2:rig.c(7491):async_data_handler_stop returning(0)
ser_set_rts: RTS=0
ser_close: restoring options
rig_close(1528): 0x13600ce1c rs->comm_state==0?=0
1:rig.c(1530):rig_close returning(0)
ft980_cleanup called

EA1FC,

Thanks for your previous post.? I appreciate the info. I have been looking at the Q03 in the RF unit. Is that the one you meant.? It is the large one near the front corner.? In GEN the emitter and base are 12.54V and the collector is 0V.? In HAM the emitter and collector are 12.54 and the base is 11.84V.? (My power supply only puts out 13.06V and 23.9V.)? All this is with the PA unit removed.

I did power it up with the PA installed but with the RF in and out both disconnected and it did not overheat like before.

I'm still looking for someone local who might be able to work on this radio.

Happy New Year!

Bob N9IB

Hope you all had a pleasant Christmas holiday

I've finished re-furbishing the PA unit following previous owners terrible mess.
Two questions please:

(i) The final amplifier bias is adjusted by turning VR8001. Page 30 (Technical Supplement) asks for setting the "High Current" line to the PA to 200mA. There are three lines feeding the board? ( a fourth is ground) - Two 13.8V and one 24V. Does anyone know which is the "high current" line please for this measurement?

(ii) PO meter calibration. This is adjusted by turning "VR 11 Main Chassis" (after setting "drive" to give 100Watt output on an external meter)? until 100W is read on Meter 1. Does anyone know where this pot. is situated please?

Thanks in advance for any help

Peter G0LQU

Many thanks Bob - I'll take a look tomorrow - but I may have to consult you a bit further down the track! I want to change the two smoothing caps.

Kind regards

Peter G0LQU

bthola@... wrote:

I don't have any other documentation but the rear cover plate over both units is removed with 6 screws.? Once the cover plate is off there are 4 screws holding each unit in.? These 8 screws are recessed in between the cooling fins.? Hope that helps.

Bob N9IB

Hello
I need to remove the power supply and power amp units from the back of the radio. I have the user intructions and the technical supplement but they do not cover this area. Is there any more documentation available please?

Thank you

Peter G0LQU

I don't mind you pointing out the obvious.? I will take any suggestions I can get.? I was aware of the MOX button and had checked it.? I will attempt some of the voltage checks you suggested. Thanks, Bob N9IB

Hi all. I have a very early FT980 (in fact I have two - one with an Rx fault with LSB and one with a Tx fault - intermittent RF power out).

For the Tx problem rig, when I Tx using FSK mode with 50 Ohm dummy load and advance the drive control - SOMETIMES - meter 1 can go full-scale (normal) and my power meter shows a steady 80 Watts Rf out. (a bit low).

OTHERTIMES there is no movement on meter 1 even with Drive control fully clockwise and no Rf out on my external power meter.

I noticed with the drive control fully clockwise on Tx, quite a loud hum from the area of the PA/Power supply which I have proved is 100Hz.

This sounds like too much ripple from the two smoothing capacitors (18000uF 50VW, which i will try to change) but I wonder if this is the cause in the intermittent problem or whether this is something else? (e.g. the tantalum capacitors mentioned by EA1FC?

Thanks for any comments

Peter G0LQU

Sorry for the obvious that follows, but it has happened to me before hahaha. There is a MOX knob that puts the radio in transmision without pushing PTT. If it is pushed in, the radio goes in TX without PTT. Maybe it can happen too with the VOX. Of course to go into TX has to be in HAM mode. So if any of the events are "ready" as soon as you go in HAM the radio goes on TX. So check that you dont have MOX or VOX ready to activate TX.

In case the radio goes on TX when in HAM, you lose reception. As I told you it had happened to me during repair. ?Why does it not receive? SILLY it was in transmission? because MOX was ON. Some modes FM FSK or CW can produce full power

Because the PA (alias "the brick") has only 3 connections, 24V for finals, 13,5V for drivers, and (switched RX/TX) TX13.5V for predriver Q01 and bias 13,5V>8V>0.7V with the two voltage regulators. It is very pasive just follows the orders, but has no decision.

You can test the PA outside the radio. and measure intensity. TX13.5V in mine was about 200mA. 24V for finals, and 13.5 for predrivers should be almost 0 without TX13.5V (reception). I have not measured intensity because mine worked OK, but I think that 24 and drivers should take about 1A each in TX (no signal out) and nothing in RX.

Check voltage out of Q01 in RF unit in RX and TX with PA out. That is the TX13.5V output to PA.

It inhibites (cuts) TX13.5V in GEN and allows transmission in HAM, I mean ALLOWS, because RL01 in RF unit is the one really switchin RX/TX. In a very brute way Q01 in RF unit can be bypassed, it only inhibites in GEN or TRANSVERTER, in other words KILLS the PA even if RL01 goes in TX, RF unit Q01 stops TX13.5V to the PA. As all is OK in GEN, I think Q01 in RF units makes its job cutting TX13.5V from RL01, even if RL01 moves from RX to TX, Q01 stops 13.5V to PA. Only when Q01 in FREE (HAM mode) you get the problem. You have to check Q01 output. If you get 13,5V in HAM RX the problem is in RL01 ?welded allways in TX? I think this is the first thing to do, and it is easy. Just disconnect the PA and open the low cover to have access to RF unit.?

As you see, nothing should change in PA unit as long as the radio keeps in RX.

Check MOX and VOX. and relay RL01 in RF unit. Maybe does not cut TX13.5V out in RX mode. Easy to check in Q01 in RF unit. just in a front corner, a large transistor, acting just as a switch.

Even so, you have a problem, because even in TX should not smoke. So when (AFTER) you clear the first part (RX/TX switching), you have to check the PA. I think something makes drivers and finals high intensity. Maybe some are damaged (short collector-emmiter) or bias that should be about 0,7V from second regulator, is extremelly high ?8V? and makes drivers and predrivers crazy.

I have repeated myself a lot hahaha, but I think the message it is clear.

73 EA1FC

This is definitely not a Tx/Rx issue.? I have not even attempted to transmit since Nov. 14th when the first problem appeared with the C20.? Everything seems OK until I switch from GEN to HAM and then it gets hot fast.? At this point I'm stumped.? Why it gets that hot in receive I do not know.

There is no one close to me that can repair this that I know of.? I would have to ship it to someone and hope they have experience with these radios.? That's why I have been doing the things I can do to try to troubleshoot this.

As far as I know, nothing changes in the PA while in reception HAM or GEN.

Maybe you mean in transmision. Then voltage TX13.5V appears (13.5V line is allways present for drivers and finals collectors). After the fac mod, predriver Q01 takes from TX13.5V too. This TX13.5V voltage is reduced for bias to 0.7V in two cascaded regulators. If they are shorted an extreme high bias can pass to the drivers and finals. And some disaster may happen. TX13.5 comes from Q01 in RF unit, via RL01 in RF unit. Check both. They made the Rx/Tx conmutation.

If a tantalum capacitor in Q01 collector shortens and the 13.5V PS protection does not work (mine lowered to 3v), RL01 may have damaged by overcourrent, because Q01 in PA takes power via this relay once the fac mod has been made. In schematic PA Q01 takes from 13.5V line, after mod it takes from TX13.5V via RF unit Q01 and RL01.

But all this is related to Tx/Rx, not with HAM/GEN.

I think the mod was done to avoid PA Q01 to autoscillate in Rx. If you get TX13.5V line with voltage during Rx (RF unit RL01 stuck), the whole PA can oscillate madly.

If it gets hot in HAM Rx... you have a problem somewhere.

I replaced the two resistors in question and now some else smoked.? It worked fine in GEN but when I selected HAM it smoked briefly.? I cannot see any damage or figure out with component caused the smoke.? It still works fine in GEN but in HAM it gets hot fast and smells hot.? Still trying to determine the source of the heat.? It is something in the area of Q05. A non-contact thermometer quickly shows a temperature of 180 F in that area in HAM mode.

73 N9IB