User's Manual

ALPHA 9500 Interim OPERATING MANUAL

www.alpharadioproducts.com

Replace all attachment screws. Use only the 6-32 screws supplied with the ampliﬁer and do not

tighten any of the screws until all are started. Do not attempt to operate the ampliﬁer with the

cover removed or only placed back on the unit without the attachment screws. This WILL cause

damage to the Alpha 9500 and may also lead to injury or death to the operator.

4.5 Ampliﬁer/Station Interconnections

Once the power transformer is installed, properly conﬁgured, and the cover replaced, place the

ampliﬁer in its operating position. Make sure it is placed on a stable surface and that there is

sufﬁcient space to the rear, sides, and top to allow good air ﬂow and safe placement of cables.

4.5.1 Coaxial Cable Types & Connectors

Connect the transceiver RF output to the ALPHA 9500 RF INPUT connector with 50-ohm coaxial cable-

RG-58C/U or equivalent. A 6 ft. cable is supplied for this purpose.

Coaxial cable from the 9500 RF OUTPUT connector to the antenna should be RG-8A/U, RG-213/U, or

equivalent high quality type with a PL-259 UHF-type plug on the ampliﬁer end. RG8X cable is not

recommended, as it is not rated for 1500 watts.

4.5.2 T/R Control Cable

The Alpha 9500 has a full break-in vacuum relay QSK system requiring only the normal

interconnection when used with a modern QSK transceiver. The Alpha 9500 requires a contact closure

(short circuit) on transmit from its RELAY jack center pin to chassis. This function is supplied by the

transceiver, usually from a dedicated relay that is normally open in receive and closed in transmit.

Shielded wire should be used for the T/R control cable. The Alpha 9500 end must be ﬁtted with a

common phono (RCA-type) plug and the other end with a connector suitable for the transceiver.

The T/R relay contact must close before application of RF drive. The Alpha 9500 protection circuitry

prevents “hot-switching” with RF drive applied. Modern transceivers have the proper time delay

between key up and the start of the transmitted signal to allow the Alpha 9500 to follow the CW

keying. If a T/R timing problem is suspected, connect the CW keyer to the RELAY jack on the Alpha

9500, and connect a cable from KEY OUT on the ampliﬁer to the keying input of the transmitter.

4.5.3 ALC