DZ HT-7, Инструкция по сборке, Страница: 39 / 44

Page 39
TROUBLESHOOTING
Before calling or emailing us for
service or help, please check the
following things.
Problems with kits are almost al ‐
ways related to soldering. Check
every connection carefully to
make sure the parts and wires are
fully soldered and the right
wires are in the right holes.
Before starting any troubleshoot ‐
ing procedure, try to narrow the
problem down to a specific area—
is it transmit ‐ related? Receive ‐
related? Both? Is it a power sup ‐
ply problem?
Check to make sure that all parts
and wires have been properly
clipped so that no leads or wires
are shorting each other or the
chassis. Look carefully for
shorted traces or pins.
Make sure that the power source
(battery or external supply) is
actually providing 10 ‐ 12VDC.
Check all electrolytic capacitors
to make sure they are inserted
with the polarity band on the
correct pin. Reversed electro ‐
lytic capacitors can draw exces ‐
sive current, and they can even
smoke!
Verify all voltages using the
chart on page 22.
A review of the theory of opera ‐
tion may also help you determine
where to look for problems.
If after going through these
steps you still cannot resolve
the problem, email us at sup ‐
port@dzkit.com or call us at 970 ‐
667 ‐ 7382, Monday ‐ Friday, 8AM to
5PM.
Problem Likely causes Solution
No receive audio No power
Check battery connections or external
power supply
Volume control pot Check solder connections to RV1
Speaker wiring Check for reversed black/white wires
Headphone jack Replace headphone jack
U2 reversed Remove and replace U2
Can't measure 11.1V RV1, PTT switch Check soldering
D3 reversed Remove and reinstall D3
Receiving AM broad-
casts
U3 pin 1 on HT-7-2 board out of
range
Adjust RV2 so that voltage is 5.5 to
7.5VDC
Weak (or no) transmit
signal
T2 and/or T3 reversed
Check T2 and T3 wiring, solder connec-
tions
Incorrect wiring from HT-7-1 to HT-
7-2 board
Verify wire colors as shown on page 21