Not gone, and not forgotten.
Crowthorne Tubes lives on.
valves
Please enquire below
We still have a quantity of radio and TV valves left. Please enquire below.
I carry out a few radio and TV repairs/restorations in the winter months when I am not playing with my classic cars.
STANDARDS CONVERTERS
The only ones now available are the Hedghog, and the specifications of these are below. (The hedghog spelling is deliberate)
HEDGHOG III
625 TO 405 LINE STANDARDS CONVERTER
FEATURES
aspect ratio conversion 4:3 => 4:3, 4:3 => 5:4, 16:9 => 4:3, 16:9 => 5:4
Selectable equalising pulses.
Audio test tones of 400Hz and 1KHz
Test card and grey scale
405 line video out (1VPP)
Requires 7.5 to 9 V DC at 250 mA (not supplied)
MODULATOR FEATURES
Frequency coverage 28.5 to 900 MHz in 5 ranges
Frequency ranges and step:
28.5 to 56.25 MHz step 15.625 KHz
56.25 to 112.5 MHz step 31.250 KHz
112.5 to 225 MHz step 62.500 KHz
225 to 450 MHz step 125 KHz
450 to 900 MHz step 250 KHz
Selectable negative video FM sound or positive video AM sound
Selectable vision/sound carrier separation of 4.5, 5.5, 6.0 and 6.5 MHz or when in positive video AM sound mode the video and sound carriers can be set independently(Variable mode)
Selectable picture/sound carrier ratio of 12 and 16 dB or fixed at 6dB when in Variable mode
Can be used as a stand alone modulator.
HEDGHOG V
625 TO 405 LINE STANDARDS CONVERTER
FEATURES
• 405 line standards converter with 4:3 => 4:3, 4:3 => 5:4, 16:9 => 4:3, 16:9 => 5:4 aspect ratio conversion.
• Selectable equalising pulses.
• Audio test tone of 400Hz
• Test card and grey scale
• 405 line video out (1VPP)
• Can store 6 image stills (Test Card C is supplied in position 6)
• Requires 7.5 to 9 V DC at 250 mA (not supplied)
MODULATOR FEATURES
• Frequency coverage 28.5 to 900 MHz in 5 ranges
• Frequency ranges and step:
28.5 to 56.25 MHz step 15.625 KHz
56.25 to 112.5 MHz step 31.250 KHz
112.5 to 225 MHz step 62.500 KHz
225 to 450 MHz step 125 KHz
450 to 900 MHz step 250 KHz
• Selectable negative video FM sound or positive video AM sound
• Selectable vision/sound carrier separation of 4.5, 5.5, 6.0 and 6.5 MHz or when in positive video AM sound mode the video and sound carriers can be set independently(Variable mode)
• Selectable picture/sound carrier ratio of 12 and 16 dB or fixed at 6dB when in Variable mode
• Can be used as a stand alone modulator
Hedghog PSC (Programmable Standards Converter)
Features:
LCD Display
Field frequencies of 25, 30, 50 and 60 Hz
Number of lines between 16 and 830
Number of active lines(lines with picture information) between 8 and 800
Adjustable length of front porch, line sync, back porch and broad pulse.
Number of broad pulses between 1 and 50.
Sync height of 20, 25, 30, 35, 40, 45 and 50%
Independent left and right crop
Selectable equalising pulses
Test patterns: Test card, Grey scale, Crosshatch, Cruciform, Black screen, White screen
Composite video input
Requires 7.5 to 9 V DC at 250 mA (Not Supplied)
Modulator Features:
Frequency coverage 28.5 to 900 MHz in 5 ranges
Frequency ranges and step:
28.5 to 56.25 MHz step 15.625 KHz
56.25 to 112.5 MHz step 31.250 KHz
112.5 to 225 MHz step 62.500 KHz
225 to 450 MHz step 125 KHz
450 to 900 MHz step 250 KHz
Selectable negative video FM sound or positive video AM sound
Selectable vision/sound carrier separation of 4.5, 5.5, 6.0 and 6.5 MHz or when in positive video AM sound mode the video and sound carriers can be set independently(Variable mode)
Selectable picture/sound carrier ratio of 12 and 16 dB or fixed at 6dB when in Variable mode
Can be used as a stand alone modulator.
HEDGHOG L
Features:
LCD Display
405/819 line standards converter combined with a stand-alone multi system programmable VHF/UHF modulator.
aspect ratio conversion 4:3 => 4:3, 4:3 => 5:4, 16:9 => 4:3, 16:9 => 5:4
Selectable equalising pulses when converting to 405 lines
405 line Test card
Composite video input
Requires 7.5 to 9 V DC at 250 mA (Not Supplied)
Modulator Features
Frequency coverage 28.5 to 900 MHz in 5 ranges
Frequency ranges and step:
28.5 to 56.25 MHz step 15.625 KHz
56.25 to 112.5 MHz step 31.250 KHz
112.5 to 225 MHz step 62.500 KHz
225 to 450 MHz step 125 KHz
450 to 900 MHz step 250 KHz
Selectable negative video FM sound or positive video AM sound
Selectable vision/sound carrier separation of 4.5, 5.5, 6.0 and 6.5 MHz or when in positive video AM sound mode the video and sound carriers can be set independently(Variable mode)
Selectable picture/sound carrier ratio of 12 and 16 dB or fixed at 6dB when in Variable mode
Can be used as a stand alone modulator.
HEDGHOG PSC
(Programmable Standards Converter)
Features:
LCD Display
Field frequencies of 25, 30, 50 and 60 Hz
Number of lines between 16 and 830
Number of active lines(lines with picture information) between 8 and 800
Adjustable length of front porch, line sync, back porch and broad pulse.
Number of broad pulses between 1 and 50.
Sync height of 20, 25, 30, 35, 40, 45 and 50%
Independent left and right crop
Selectable equalising pulses
Test patterns: Test card, Grey scale, Crosshatch, Cruciform, Black screen, White screen
Composite video input
Requires 7.5 to 9 V DC at 250 mA (Not Supplied)
Modulator Features:
Frequency coverage 28.5 to 900 MHz in 5 ranges
Frequency ranges and step:
28.5 to 56.25 MHz step 15.625 KHz
56.25 to 112.5 MHz step 31.250 KHz
112.5 to 225 MHz step 62.500 KHz
225 to 450 MHz step 125 KHz
450 to 900 MHz step 250 KHz
Selectable negative video FM sound or positive video AM sound
Selectable vision/sound carrier separation of 4.5, 5.5, 6.0 and 6.5 MHz or when in positive video AM sound mode the video and sound carriers can be set independently(Variable mode)
Selectable picture/sound carrier ratio of 12 and 16 dB or fixed at 6dB when in Variable mode
Can be used as a stand alone modulator.
Email for current prices
VINTAGE COMPONENTS
Various vintage components available, including strange valve sockets
Please contact me for further information at crowthornevalves@aol.com