SG2020 Known Bugs or Problems
Frequency reads 66MHz ; memorized channel frequencies and "bands" lost.
|Cause: Intermittant loss of DC power or low voltage during transmit
Follow this procedure---
A. Power down and re-start, with proper 12VDC power.
B. Press and hold CMD
C. Press and release MEM
D. Release CMD
E. Wait and watch frequency readout for all memorized channels to be
scanned. This can take up to 5 minutes, but is usually only about 1 minute.
F. Press LIGHT
This procedure should restore all memory channels and normal operation.
If problem returns, check power supply and DC connection or battery capacity.
Muffled audio feedback in SSB or thumping in CW from speaker or headphones
|Cause: RF energy getting into internal transceiver audio path.
High SWR, radiation from the coax feedline, or placing the antenna feedpoint
or radiating elements very close to the transceiver or microphone can make
this problem worse.
A. Lower the SWR AT THE ANTENNA. Antenna tuners at the radio
may or may not solve this. Antenna coupler or better match at the antenna
sometimes helps. Add thick braided ground connection to vehicle chassis
or earth ground from one of the 4 screws on the back of the chassis.
B. For headphone use, add an in-line variable attenuator between
the headphone jack and the headphones. Suggestion: use Radio
Shack part #42-2459 "Headphone Volume Control". Cost is about $US6.
C. For CW, add an external Thump Filter between headphones and
2020 speaker output jack. See MODS
section of this website for details.
D. For SSB only, microphone can be modified to switch open speaker
audio connection when in transmit mode, or a communications-type handset
can be used with muting earpiece.
E. When all else fails, add ferrite clamp-ons to all leads as
they connect to the transceiver. DC, microphone, earphone, CW key. Add
"current balun" to coax feed.
This is a possible minor circuit design issue. Not a major problem,
and in most cases can be minimized by moving the setup or changes to the
antenna or feedline.
Internal LED SWR meter reads high SWR or incorrect output power under
all conditions, including known low SWR. Transmitter output is actually
Transceiver functions normally otherwise.
|Cause: Appears to be caused by operation at maximum power (25)
into SWR above 2:1 in the range of 7 to 18 MHz.
Fix: Replace blown diodes or other parts in the internal directional
coupler circuit (factory service).
Notes: Some users avoid this problem by always checking SWR
first in low power mode, always using an automatic antenna tuner/coupler,
or by never using a power setting above 17 in the range of 7 to 18MHz.
In 3.5MHz range, frequency jumps to 2MHz for a few hertz of tuning
Fixed by factory software Version 1.03 and above.
Other functions lost.
Fix: Factory Service.
Notes: Few cases of the "8950" problem have been documented.
More info is needed.
|Cause: Unknown. Occurs on power up.
Fix: Seems to be temporary (goes away after pressing buttons
randomly and power reset).
Notes: Only a few cases of this reported.