Delta Electronics 6730E & 6732E 1-5/8″ EIA Coaxial Transfer Switch

Summary

Introduction

The Model 6730E and Model 6732E Coaxial Transfer Switches are double-pole, double throw, high power switches for use with 1-5/8 inch 50 Ohm transmission line. The manually or remotely operated transfer switches enable the changing of coaxial connections between transmitters and antennas/dummy loads with a minimum of changeover or off-air-time. Transmission line switching occurs in approximately one second. The Model 6730E operates with 120 VAC, 50/60 Hz main power and the Model 6732E operates with 220/240 VAC, 50/60 Hz main power.

Description

Coaxial transfer switches are used to switch transmitters, transmission lines, antennas, dummy loads and auxiliary equipment quickly and efficiently when failures occur, when operating procedures are changed, or during scheduled maintenance periods. They also simplify equipment tuning, testing, and emergency repairs by facilitating quick checks under actual operating conditions.
Many switching requirements in a station are greatly reduced by the use of transfer switches. In complex systems, only one-third or one-fourth as many transfer switches are needed to accomplish the same switching function as a system using SPDT or SP3T type switches. If only three of the terminals in the Model 6730E or 6732E switch are employed, the switch can be used as a SPDT type.

The Coaxial Transfer Switch provides two isolated interlock circuits for each switch connection that duplicate the RF path exactly. All interlock switches open before the RF contacts open, and close after the RF contacts close to prevent switching with RF power applied. Additional internal switch contacts enable remote control and status indication. All interlock, indicator and control circuits interface the transfer switch through a connector.

The transfer switch can be remotely controlled using either a high level, direct AC main power switching interface or a low level, open collector/contact closure interface. The Model 33630A Coaxial Switch Control Panel controls either a Model 6730E or Model 6732E Coaxial Transfer Switch and indicates the switch connections. The control panel operates with 120 VAC or 220/240 VAC, 50/60 Hz main power and mounts in a standard equipment rack space of 3-1/2″ high by 19″ wide.

Features

Model 33630A Coaxial Switch Control Panel

Optionally, the transfer switch can be supplied with internal relays to provide an open collector or contact closure interface for low level control applications. The low level control signal needs to be maintained only for the duration of the switching cycle. Low level interface relays for operation with either 12, 24 or 48 VDC control circuits are available. Consult the factory with your requirements.

The transfer switch may be optionally equipped with 7/8 inch EIA connectors in place of the standard 1-5/8 inch EIA connectors on any or all four ports. This option enables the switch to directly interface 50 Ohm transmission lines terminated with 7/8 inch EIA flanges without requiring the use of line reducing connectors.

Technical Specification

MODEL NUMBER

6730E

6730E1

6732E

6732E1

Termination, Male EIA Flange:

Standard
Optional

1-5/8 in
7/8 in

Frequency Range, MHz:

0-400

0-900

0-400

0-900

Impedance, Ohms:

Average Power Rating*, kW:
@ 50 MHz
@ 108 MHz
@ 400 MHz
@ 900 MHz

20
13.6
6.4
—

20
13.6
6.4
5

20
13.6
6.4
—

20
13.6
6.4
5

Peak Power Rating*, kW:

145

VSWR, Guaranteed Max.:
0-216 MHz
216-400 MHz
400-900 MHz

1.02
1.03
—

1.02
1.03
1.06⇔

1.02
1.03
—

1.02
1.03
1.06⇔

Isolation, Typical, dB:
0-216 MHz
216-400 MHz
400-900 MHz

60
55
—

60
55
40

60
55
—

60
55
40

Insertion Loss, dB:

0.1

Switching Time, Seconds:
Maximum
Typical

2
1

Pressurization

Power Source:

120 VAC ±10%,
50/60 Hz

220/240 VAC
±5%, 50/60 Hz

Optional Interface Relay Operation Power, Nominal, Watts:

Power Drain, Watts (during switching):

Interlock Contact Rating:
@ 24 VDC/120 VAC@ 240 VAC

7 Amps Res,
5 Amps Ind
6 Amps Res,
4 Amps Ind

Dimensions:
(L x W x D)
Inches
mm

8 x 8 x 10
200 x 200 x 250

Weight:
Pounds
kg

13
6

Order Numbers:

Switch with 4 standard
1-5/8″ EIA connectors

961-0020-001

961-0020-003

961-0020-002

961-0020-004

Switch with 4 optional
7/8″ EIA connectors

961-0020-005

961-0020-007

961-0020-006

961-0020-008

Model 33630A Coaxial
Switch Control Panel

913-0069-001

913-0069-002

Low Level Interface Relays	12 VDC	24 VDC	48 VDC
Factory Modification Kit	942-0087-001	942-0087-002	942-0087-003
Field Modification Kit	942-0094-001	942-0094-002	942-0094-003

*	At unity VSWR and 40° C (104° F) ambient temperature. Average and peak power ratings apply to switches equipped with standard 1-5/8″ EIA connectors. For any port equipped with the 7/8″ EIA connector, the average power ratings are 6.8 kW at 50 MHz, 4.6 kW at 108 MHz and 2.4 kW at 400 MHz. The peak power rating for any port equipped with the 7/8″ EIA connector is 60 kW.
⇔	Adjusted for a specified 10 MHz band. VSWR may be higher at other frequencies.

Delta Electronics 6730E & 6732E 1-5/8″ EIA Coaxial Transfer Switch