FILTERS, SUPPRESSION

Used to suppress Radio Inference.  Fitted with a 0.1uf capacitor and a 11ohm choke.

The No. 6A is fitted as standard on the Bell No. 65A which is part of Telephones No's 326, 327 and 392.  This filter can also be fitted when required.

The Filter No. 6B is used to suppress interference from Telephone dials.

See EI Telephones, General D5901.

Drawings - 61280 (No. 6) and 62884 (No. 6B).

Specification - D1229.

Used to suppress Radio Inference from the motor governor circuit on Teleprinters No. 7.

Drawing - 64934.

Used to suppress Radio Inference from Motors on Teleprinters No. 7.

Used to suppress interference from the transmitting contacts on a Teleprinter No. 7.

Drawing - 64637.

This a filter fitted to DC bells.

It is a standard fitment in Bells, No's 43A, 56A, 56C & 56E and Buzzers No. 16 & 20.    This filter can also be fitted when required.

Used to suppress interference from the send-receive switch circuit on a Teleprinter No. 7.

Used to suppress radio interference.

For suppressing interference from telegraph broadcast relays.

Diagram - TG1184

For radio interference suppression on mains operated portable appliances which incorporate thermostat control. Multiple stage filter. For permanent fixture at control points.

Rating - 1amp. max.

Includes:-
1 x Case, Filter Suppression, No. 18A.

For radio interference suppression on mains operated portable appliances which incorporate thermostat control. Single stage filter. For connection in flex leads.

Rating - 400rnA. max.

Radio interference suppressor. Consists of 2 capacitors in a metal or moulded case.

Wire connections

250 V.A.C. working.

A - 0.1+0.1uF.
B - 0.2+0.2uF.
C - 1.0+l.0uF.
 

For radio interference suppression.

A 9' length of rubber or P.V.C. covered cable with a radio interference suppressor moulded into the lead about 1' from one end. For R.F. Suppression at TV Frequencies.

No. of conductors and rating - 3 core / 1amp max.
Type of suppressor: Inductor R.F. No. 12 - 1amp.

Drawing - WM 19.

Specification - W3817.

Used to suppress Radio Inference from DC bells.

Fitted to Telephones No's 306, 326 and 392.

For suppressing radio interference voltages of asymmetrical form.

Dimensions - approx. 1.5" x 0.75" x 0.5".

Rating - 0.75amps continuous.

Connections - Wire ends.

For suppressing radio interference voltages of asymmetrical each form.

Dimensions - approx. 2" x 1.25" x 1".
Rating - 2.0amps continuous.
Connections - Wire ends.

For suppressing radio interference voltages of asymmetrical form.

Dimensions - approx. 2"x 1.75" x 1.75".

Rating - 3.0amps continuous.

Connections - Wire ends.

 

Used to suppress interference from sewing machine motors. each
Primarily for use at T.V.F.

Comprises:-
1 x  Bakelite box 1.25" x 1.1" x 0.6".
1 x Capacitor 0.025uF.
2 x Inductors, R.F., No. 15A.

Connections:-
2 x Terminals.
2 x Flex leads 4.5".

For fitting to M.C.V.F. Type 4 channel panels. For suppressing
radio interference from Relays, Polarized No. 2B/103

Includes:-
1 x Capacitor, Paper No. 7518.
1 x Filter, Suppression No. 30A.
1 x Inductor, R.F. No. 11-0-5 amps.

Used to suppress Radio Inference.

I.F. filter for use in T.V. receivers where interference each break-through is suspected.  Fitted in the aerial lead.

Metal cased with co-axial input and output connections.

Used to suppress Radio Inference.

I.F. filter for use in T.V. receivers where interference each break-through is suspected.  Fitted in the aerial lead.

Metal cased with co-axial input and output connections.

Used to suppress Radio Inference.

For suppression of radio interference from contact devices.

To reduce interference to T.V. receivers arising from I.F. breakthrough and also from "scatter" effect.  Fitted in the aerial lead.

Metal cased with co-axial input and output connections.

For insertion in aerial input lead to the receiver when adjacent signal interference is suspected.

1A - 35-50Mc/s. T.V. receiver.
2A - 45-100Mc/s. T.V. receiver and F.M. receiver.
3A - 110-220Mc/s. T.V. receiver.

For reducing the effects of interference voltages entering a T.V. receiver via the outer screen of the coaxial lead.

For suppressing radio interference voltages of asymmetrical form. Insertion in mains lead 200/250V.

Rating - 0.75 amps.

For suppressing radio interference voltages of asymmetrical form. Insertion in mains lead 200/250V.

Rating - 3 amps.

For suppressing radio interference. Frequency range 200kc/s-15Mc/s.

Rating - 15 amp. max.

Used to suppress Radio Inference.

Used to suppress Radio Inference.

For suppressing radio and T.V. interference in connexion with Telegraph apparatus.

Coaxial cable wound on a. ferrite core, for reducing T.V. interference.

1A - 3MHz - 40MHz.
2A - 40MHz - 220MHz.

Used in Cx aerial feeder of VHF T.V. receivers for rejection of unwanted signals in the range 70-90 and 130-170MHz. Tuneable.

Band-stop filter used in the Cx aerial feeder of VHF T.V. receivers to reject unwanted signals in the range 72-88MHz (P.M.R. installations, etc.)

Unbalanced band-stop filter giving attenuation over the range 130-165MHz. Used to protect radio and T.V. receivers from high level amateur and "land mobile radio" transmission.

High-pass filter used in the Cx aerial feeder of VHF T.V. receivers to reject unwanted signals from High Level HF and VHF transmissions.

Cut-off frequency - 470 MHz

Tuneable notch filter to provide attenuation in range 400-860MHz. Used to reject unwanted high level transmissions adjacent to Band IV and V television channels.

Broad band attenuating filter to reduce interference entering a T.V. Receiver via screening braid of Coaxial Aerial Feeder.