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60lpi may give a dark image to pictures.. WARNING! DANGER OF ELECTRICAL SHOCK Opening mains operated equipment like the HHB Circle 5A incurs a risk of electric shock. DO NOT attempt to open this equipment unless you are qualified to do so, have the necessary test equipment and are operating the Circle 5A from an ISOLATED POWER SUPPLY.
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Contents Page 1: The cover and warning Page 2: (This) index page Page 3: Section 1.0: External arrangement and comments on connectors/controls Page 4: Section 2.0: General arrangement, notes on testing Page 5: Section 3.0: Access to the Circle5A electronic module Page 6: Section 4.0: General inside views of C5A module Page 7: Section 4.1...
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0.775V, it is expected that in most situations the Circle 5A’s vol- ume control wil be set to about half way i.e. 12 o’clock. This would apply in many studio’s where the ‘+4’...
2.0 General arrangement All the signal processing circuitry of the Circle5A amplifier module is arranged on two PCB’s - one ‘passive’ board, the C5AIPM holds the XLR, selec- tor switch, volume control and phono socket. This is connected to the C5APAM (filter/PSU/power amp) board via a 6 way wire loom.
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Sec 3.0 Removing the Circle 5A’s Section 3.3: Removing the screws active module from the cabinet Please follow these instructions exactly. Failure to do so may well destroy your cabinet and/or It is absoluletely essential that before removing module. the module you have the necessary tools, a clear space, and sufficient uninterrupted time to work.
Sec. 4.0 General view of C5A module viewed from the inside There are four function blocks in the C5A elec- The input signal, once selected by the user tronic module: switch is sent to the C5APAM C5AIPM: a small PCB carrying the XLR, MAINS TRANSFORMER: phono,volume control and selector switch.
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Section 4.1 Close-up views of inside of C5A module C5AIPM: note air holes are sealed with hot glue. Wire loom connecting C5AIPM to C5APAM C5APAM...