DELTA - 4C Console
Lightning Surge Protected 4 Position RF Coax Switch
with field-replaceable surge protection pill

The Model Delta-C Console switch is a precision RF Switching device employing the latest High Technology designs



SWITCH POSITIONS Four, two either side of a "common" center connector.
LIGHTNING SURGE PROTECTION Alpha Delta Model D-4 internally mounted, f ield- replaceable ceramic gas tube
Arc-Plug® Cartridge Pill.
SPECIAL SWITCHING FUNCTIONS When the knob points to the center (ground) switch position, all antenna circuits are internally disconnected and grounded. When the knob is in an active position, the unused antenna ports are grounded. The active position circuit is continuously protected by the Model D-4 Arc-Plug® Cartridge Pill.
GROUNDING REQUIREMENTS A separate, external ground wire must be attached from the ground stud on the rear of the switch to the station ground system. (not the equipment chassis.) The Arc-Plug® Cartridge Pill will not operate without a good ground. It is also good practice to ground the coax shield at point of entry to the building.

Nominal (SO-239 CONNECTORS)

  VSWR dB Loss dB Isolation
30 MHz <1.11:1 .1dB .1dB >60dB
150 MHz <1.3:1 .1 5dB >50dB
450 MHz <1.4:1 .5dB 50dB



Additional D-4 Arc-Plug® Cartridge Pills are available from Alpha Delta or your dealer at a nominal cost. Replacement in the field is quite easy, and the only tool required is a screwdriver.

Should a severe lightning hit occur, the ceramic gas tube Arc-Plug® Cartridge Pill will short to ground protecting your equipment. The pill will remain shorted however (unlike its recovery to open circuit condition after a less severe hit or transient) and must be removed or replaced in order to continue operation. If replacement pill is not immediately available you can continue operation (without lightning transient protection) by removing the shorted pill from the switch until you obtain its replacement.

To replace the pill, use a screwdriver to remove the front panel access screw by turning it counter clockwise. Then, turn the switch upside down until the Arc-Plug® Cartridge Pill drops out of the access hole. Now, turn the switch right side up, drop the new Arc-Plug® Cartridge Pill into the access hole. (Make sure the Pill is lying with its metal surface up) then, insert the set screw and tighten it in a clockwise direction with the screwdriver until finger tight. (CAUTION-Over tightening of the set screw can damage the Arc Plug® Pill.)

Note: The Alpha Delta Model D-4 Arc Plug® Cartridge Pill is designed to reduce the hazards of lightning induced, or other high voltage induced surges. This device, however, will not prevent fire or damage caused by direct lightning strike to an antenna, power lines or other structure.

Caution: Do Not change switch positions while RF is applied. This can cause damage to the switch contacts and such damage will not be covered by our warranty.


The model Delta-4C switch can be used in several different applications, depending upon the installation configuration.

Note: Switch specifications, including co-channel isolation in dB, are guaranteed only when using properly installed 50 ohm coaxial cable. Single wire "jumpers" or antenna feeds do not provide proper isolation or VSWR characteristics. For transmitting, any model must be placed at a point in the coax line where VSWR does not exceed 2:1 to prevent high RF voltages from triggering the Arc-Plug® Pill.
Note: There are no user serviceable components inside the switch. Do Not tamper.

Seller warrants that each unit sold is manufactured in accordance with seller's specifications, drawings, samples or data in effect on the date of receipt of the order, as they apply to those parts called for on the order, and that each unit is free from defects in materials and workmanship. Sellers liability under this warranty is limited to the repair or replacement of any unit which proves to be defective in material or workmanship under normal use and service provided the unit is returned to the Alpha Delta shipping point ( or authorized distributor if purchased through this source) within six months from date of shipment, and will in no case be responsible for special or consequential damages including but not by way of limitation, cost of removal of units from or installation in equipment. This warranty is in lieu of all warranties expressed or implied.