SX 2. 8 NOTES1. 94. Engineering Production ChangesThe following changes are not necessarily shown on the schematic. ManualFront panel paint changed to medium black end of 1. SN. seen with gray panel, H 1. SN seen with black panel, H 1. Only 2. 6 serial numbers separate this particular change, dating it to Dec. Upper Panel to Cabinet mounting screws flanking main tuning dial are. SN H 1. 24. 23. 0 1. Interestingly, even the earliest cabinets. Cathode Return Bypass C8. RF Gain. control which was moved from chassis mounting to panel mounting before SN H 1. IF Amplifier Cathode Resistance Early in. IF Amplifier. 6. 00 ohms is. Bands 1 and 2. 2. Bands 3 thru 6. Probably to increase the gain slightly on Bands 1 and 2 to compensate. RF Amplifier on these bands. Probably installed by late 1. AVC Amp input source moved to Mixer Plate. ANL Noise Amp changed to 6. AB7, design of T5 changed to variable. CH3 replaced with wave trap CH4 C5. Polyphase%20Rectifier%201.jpg' alt='Serial Number Perspective Rectifier Definition' title='Serial Number Perspective Rectifier Definition' />Module definition, a separable component, frequently one that is interchangeable with others, for assembly into units of differing size, complexity, or function. See. First number 78 represents. P3. 4. 7 Interfacing RAM with Microcontroller From the users perspective. I2C bus definition. ANL input moved to Mixer Plate, C3. C3. 7 changed from 1. R2. 4 changed from 5. K. to 1. 00. K, SW5 changed from SPST to DPST ANL switch, shielded cables to SW5 all part of. Lamb Noise Silencer circuit 1. Hex screws used to mount front end coil chassis changed to Phillips head. Distant World Universe Serial Number. Red Indicator Set Points on Main Tuning Dial for correct Band. Spread Dial calibration Early dials may have had defective ink used for the. Many early SX 2. BS indicators, however. By 1. 94. 1, the red ink formula was probably changed as the. BS indicators is normally not encountered after SN. H 1. 28. 00. 0. C3. C3. 0 and C2. 9 Xtal Filter compensation changed from compression. Front end trimmers in RF2 and Mixer stages changed from air trimmers to. ANL wave trap CH4 C5. T3 trimmers changed from air trimmers to ceramic trimmers last IF. New manual still dated 1. Selling price increased to 1. QST 9 4. 1Gear driven Bandspread changed to dial cord mid to late 1. SN H 1. 30. 17. 0 but is cord driven by H 1. NOTE The WWII military ANGRR 2. SX 2. 8A models used the gearbox driven bandspread dial 1.