Aa7b • 1 all band hf, vhf, uhf active antenna ramsey electronics model no. Aa7b great for perking up scanner reception. Circuit based on true active antenna research. Performance rivals units costing many times more! Front panel rf gain control. Uses dual gate mosfet technology for low noise hf ampl...
Aa7b • 2 partial list of available kits ramsey transmitter kits fm10c, fm25b fm stereo transmitters fm100b super pro fm transmitter mr6 model rocket tracking transmitter am1, am25 am transmitters ramsey receiver kits fr1 fm broadcast receiver ar1 aircraft band receiver sr2 shortwave re...
Aa7b • 3 aa7b active antenna kit ramsey publication no. Maa7b manual price only: $5.00 table of contents circuit and device description.................................. 4 parts layout diagram ............................................... 7 ramsey “learn-as-you-build” assembly strategy .. 8 schema...
Aa7b • 4 circuit description the aa7b is the next generation of our popular aa7. While the aa7 is a great product it has been around for a long time in relative terms of electronic equipment. Because of ever changing technology there comes a time when certain components are no longer produced and th...
Aa7b • 5 the amplifier on the left side of the circuit you will see j1. This is where the receiving antenna is connected. The signal(s) picked up by the antenna are connected to u1 pin 5 through a .01uf coupling capacitor. This capacitor is necessary to isolate u1 from any dc levels that might be pr...
Aa7b • 6 to q3 pin 4 from the antenna. The last thing in the signal path is u5, another electronic relay like u1. The signal from q2 is coupled to pin 1 of u5. For this discussion u5, like u1, is configured to connect pins 1 and 5 together and the signal connected through c12 to the output jack j2. ...
Aa7b • 7 rev 1.2 ramsey electronics, llc active antenna aa7b parts layout diagram.
Aa7b • 8 ramsey “learn-as-you-build” assembly strategy be sure to read through all of the steps, and check the boxes as you go to be sure you didn't miss any important steps. Although you may be in a hurry to see results, before you switch on the power check all wiring and capacitors for proper orie...
Aa7b • 9 all in one unit. As with all rf circuitry, we want to mount the parts as low as possible to the board. A 1/4” lead length on a resistor not mounted close to the board can act as an inductor or an antenna causing all sorts of problems in your circuit. Be aware though that there are stand up ...
Aa7b • 12 aa7b active antenna kit parts list capacitors 14 .01 µf disc capacitor (marked .01, 103 or 10nf) [c1-4, c6-15] 2 10 µf electrolytic capacitor [c5,c16] inductors 2 22 µh (red-red-black) [l1,l2] resistors 1 220 ohm (red-red-brown) [r7] 1 6.8k ohm (blue-gray-red) [r11] 2 10k ohm (...
Aa7b • 13 assembly instructions the following assembly steps are given in accord with the learn-as-you- build philosophy for ramsey kits. To the extent that is reasonably possible, parts are installed in the order of signal flow as depicted on the schematic diagram, with some discussion of the compo...
Aa7b • 14 16. Install r6, 100k ohm [brown-black-yellow] to the right of c6. 17. Install c8, .01 µf (marked .01, 103 or 10nf) to the right of r6. 18. Install l2, 22 µh [red-red-black] to the right of c8. 19. Install c9, .01 µf (marked .01, 103 or 10nf) to the right of l2. 20. Install c10, ....
Aa7b • 15 mounted flush to the board. Install the part so that it is as high above the board as possible. Solder the leads into place. The led will eventually be lining up with a hole in the front panel and may need to be adjusted. 35. Install the battery hold-down clamp — be sure not to use too m...
Aa7b • 16 or random wire with earth ground or counterpoise, a vertical whip of some kind, a slinky, or even a pair of alligator clips at the end of your coax line, ready to be clipped to any large metal surface that may be handy, from screen doors to bed springs! This accessory for your aa7b will he...
Aa7b • 17 very carefully and see if you notice anything unusual. Since these are pre-installed factory parts and under warranty call ramsey electronics for advice on how to proceed. If you attempt to repair these devices and damage them without contacting ramsey technical support you may void your w...
Aa7b • 18 aa7b specifications frequency of operation: 1 mhz to 800 mhz bandwidth: >800 mhz gain: 1 to 150 mhz: >20 db* 150 to 400 mhz >12 db* 400 to 500 mhz >10 db* 500 to 800 mhz >5 db* rf input jack type: bnc max signal : -20 dbm, 0.01 mw rf output jack type: bnc max signal: 0 dbm, 1mw power suppl...
Aa7b • 19 the ramsey kit warranty 1. General: notice that this is not a "fine print" warranty. We want you to understand your rights and ours too! All ramsey kits will work if assembled properly. The very fact that your kit includes this new manual is your assurance that prior to release of this kit...
Aa7b • 20 aa7 active antenna quick reference page guide circuit description ................................... 4 parts layout diagram ............................. 7 schematic diagram................................. 10 parts list ................................................. 12 assembly instru...
