The Racal RA1218 is one of the series of second generation receivers made during the 1970,s. Electrically the circuit of the RA1218 is very similar to the RA117,incorporating the Wadley Loop system,but mechanically it is very different.The RA1218 much like an RA1217 but with a Digital Readout for the frequency display.
Construction is of modular design,which may present a problem when servicing the set when faulty.If,however you have a spare module then down time can be very short indeed.All circuits are solid state,except the digital display , which is a mixture of linear IC's and Nixie Tubes.
Operation is virtually the same as the RA17/RA117 with all the usual controls.The main difference comes with sideband operation,the RA1218 has selectable upper and lower sideband filters.The bandwidths are different to the RA117,with the three settings of 8kc/s,3kc/s,200c/s fitted as standard,and there are 3 levels of A.G.C,Short,Medium and Long.
| Frequency Range | 1-30 Mhz (200khz with reduced sensitivity) |
| Resetting Accuracy | +_ 10 hz using fine tune control |
| B.F.O | +- 3Khz |
| Frequency Stability | +-50 hz over 8 hrs after 2hr warm up at constant temp |
| Antenna input | 75 ohm |
Theoretically this set should have better frequency stability over its valved counterparts as it has no valves to gradually warm the chassis up.I have found, however, that drift can still be a problem over the short term until everything has stabilized itself.Even trying 3 different VFO units produced very similar results,the set drifting hf by 1.5 kcs or so over about 1 hr.
I have spoken to a number of people about this set,some like them others hate them.I prefer the ability to select upper or lower sideband and the digital display does show you exactly what frequency you are on (you don't have to keep calibrating the scale as you do on the RA17/RA117). RF performance however can be a bit disappointing if you are used to the bomb proof front ends of the valved sets.An ATU is virtually essential when tuning near strong signals and the preselector some times needs careful tuning to make sure you have peaked on the wanted signal.More use has to be made of the RF attenuator than on the valved sets.Having said this,the RA1218 is a nice receiver and will still out perform many amateur sets of the same vintage.It is still quite a heavy radio 23kgs(50lb) and draws about 70 watts in power.
The rear panel has a number of input and output sockets for external vfo's and adaptors.
Here you can see the inside of the RA1218.The photo on the left has the display assembly in place,the other on the right with it lifted clear,and, with the exception of the 5 MHZ standard (grey box behind and to the left of the meter) you can see it is virtually identical to the RA1217
Racal also made an RA1219 which was much the same as the 1218 but had a "RACALATOR" to lock the the VFO to cancel drift.
RA1218 Variants.
| RA1218/A | Standard set with 0.2 , 3.0 , 8.0 Khz Bandwidths |
| RA1218/B | With dial Locks Removed. |
| RA1218/C | With 455 Khz I.F |
| RA1218/D | Fitted with Bandwidths of 200 hz,1.2 khz,6.5 khz, 13 khz |
| RA1218/A DA40902/A | With 1 Watt AF output |
| RA1218/B DA40902/B | 1 Watt version less dial locks |
| RA1218/C DA40902/C | 1 Watt version but with 455khz I.F |
| RA1218/X | G.C.H.Q Version |
| RA1218 DA40841 | Fitted with bandwidths of 0.2 , 0.5 , 1.2 , 3 , 8 khz less dial locks |
| RA1218 DA41873 | Fitted with bandwidths of 0.2 , 1.2 , 3 , 8 , 13 Khz. MOD Navy. |
| RA1218 DA42563 | Fitted with bandwidths of 0.2 , 1.2 , 3 , 6.5 , 16 Khz |
| RA1218 DA42441 | Fitted with bandwidths of 0.2 , 0.5 , 3 , 8 Khz |
| RA1218 DA43666 | Fitted with bandwidths of 0.2 , 3 , 8 , 13 Khz |
| RA1218 DA43779 | Fitted with bandwidths of 0.2 , 1.2 , 3 , 8 Khz |
| RA1218 DA42958 | Fitted with bandwidths of 0.2 , 0.5 , 1.2 , 3 , 13 Khz |
| RA1218 DA45271 | Fitted with bandwidths of 0.2 , 0.5 , 3 , 8 , 13 Khz |
| RA1218 DA43778 | Fitted with bandwidths of 0.2 , 0.5 , 1.2 , 3 , 8 , Khz. 1 watt output |
19/10/99.
Updated 05/03/2002