c) General Troubleshooting Tips
This section provides some general troubleshooting tips that may be helpful if a rig is
not functioning properly.
Caution: Potentially lethal voltages are present in most vacuum tube radios. Exercise
extreme caution when attempting to service this type of radio. Also, vacuum tubes
become very hot during operation and can cause burns.
c.1. The Unit Appears Completely Dead
If the unit appears completely dead, it may indicate a lack of power. Check the following
items:
Is the unit properly connected to an HP-23 Power Supply?
Is the HP-23 Power Supply plugged into a functioning wall outlet?
Is the Power switch on the HP-23 set to the 300v position? Earlier models of the HP-
23 had a three-position toggle switch 250v – OFF – 300v. Later versions of the HP-
23 eliminated this switch. It is easy for the switch to be accidently bumped to the
OFF position.
Is the power switch on the radio turned on? Is the power switch defective (not
uncommon)?
Are any of the pilot lights on? Any of the tube filaments glowing? Are the tubes
themselves hot?
c.2. Does The Unit Receive?
Many of the circuits are used for both transmit and receive. If the rig receives correctly,
a considerable portion of the circuitry can be eliminated as the cause of the problem. If
the rig does not receive correctly, it is easier to troubleshoot the problem in receive
mode versus transmit mode.
c.2.1. Unit Does Not Receive At All
Make sure that power is on and a speaker (or headphones) is connected. Using
headphones while troubleshooting is NOT recommended due to the potential shock
hazard.
Make sure that all of the tubes are fully seated. It is easy for tubes to become
dislodged during shipping. Try gently wiggling each tube while power is on – if you
hear static or a crackling sound, it probably indicates a bad connection between the
tube base and socket. If a tube is not warm to the touch, it may indicate a bad tube.
General Troubleshooting Tips revised 12/17/2021 Page 26
To Next Page
Loading...
Need help?
General
