. 123 -
EQ5 VIDEO FR:~QUENCY EQUALISERS
Portable Variable Equaliser used with TE1/502 to obtain
values of components for EQ5/503. Loss variable in 10
steps from 1dB to 20dB. DD 1957. DD Spec 6.68. ACO.
Fixed Equaliser w1th printed circuit on which appropriate
components are mOlnted for a particular line as determined
by tests with EQ5/50l and TE1/502. DD 1957.
DD Spec 6. 71. Ace. OBSOLESCNET.
As EQ5/503 but filted in metal box for mounting on PN3/2
panel. DD 1958. DD Spec 6.71. OBSOLESCENT.
Similar to EQ5/51U but constructed on printed circuit
board in CH1/12A ::or use" in EP1/ 504. Indexing pegs 17,
30. DD 1965. DD Spec 7.96. OBSOLESCENT.
Similar to EQ5/51) but fully equipped to equalise l80m of
PSF1/2. DD 1968. WITHDRAWN.
Variable Phase Eq;laliser used in EQ1/505. Provides phase
correction in 8 3witched steps at resonant frequencies in
megaherz intervale from 3MHz to lOMHz inclusive. CH1/12A,
pegs 9, 10. DD 1963. DD Spec 6.94. DDHB 6.48. ACO.
Amplitude Equaliser and filter used in RC4M/503. CH1/1ZA.
DD 1965. WITHDlUWN.
Bode Equaliser used in EP8/50l, EP8/50lA. Provides either
positive or negative loss correction. Requires 45dB of
flat video gait to compensate for loss in equaliser
sections. 483mm x 267mm panel. DD 1965. DD Spec 6.109.
DDHB 6.73. ACO. OBSOLESCENT.
Chrominance Equaliser used in EQ12L/50l to provide
continuously va, 'iable gain or loss at chrominance
frequencies, w!1:h no phase errors, so as to remove
saturation fluctuations at the end of a video circuit.
CHl/12A. DD 196'. DD Spec 11.28. ACO. OBSOLESCENT.
Delay Line Equlliser used in EP1/505 for equalising
signals, after demodulation, from quartz delay lines.
CH1/l2A. DD 1967. WITHDRAWN.
Fine Trimming ~ine Equaliser used at the receiving
terminal of 625 line colour vision links for fine trimming
of gain, chromin3.nce/1iminance gain inequality and delay
DD Spec 6.140.
Cable Equaliser, 750, for correcting frequency response of
coaxial cable lines with loss of up to ldB at 4.43MHz,
equivalent to 5lm of cable PSF1/2 or 45m of PSF1/3. Box
60mm x 2lmm x 6Cmm. DD 1968. DD Spec 8.290. DDHB 8.255.