Hertz to Metres Conversion

3AK or 1500 kHz (199.9 metres)
7ZL or 600 kHz (499.7 metres)
3XY or 1420 (211.1 metres)

Necessity for conversion charts

The vast majority of Australian valve radios and most of the late transistorised radios have the station name marked of the dials.

Stations moved around and you need to know when the movement took place and roughly when the radio was made. Australia changed to a 9 kHz spacing for AM radio frequencies on the 23 November 1978 , as part of the Geneva Frequency Plan of 1975. This change moved all AM stations to new frequencies, resulting in a staggered change across the dial (for example, 10 kHz stations moved to the nearest 9 kHz slot) and creating twelve new medium wave channels. 

For aligning a radio two frequencies are usually given, Australian service manuals often list 3AK or 1500 kHz (199.9 metres) and 7ZL or 600 kHz (499.7 metres). Sometimes 3XY or 1420 (211.1 metres) was listed.

Overseas radios present a problem if they are marked in metres and local stations. This mainly relates to European sets. 

Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres
540	556	700	429	860	349	1020	294	1180	254	1340	224	1500	200
550	545	710	423	870	345	1030	291	1190	252	1350	222	1510	199
560	536	720	417	880	341	1040	288	1200	250	1360	221	1520	197
570	526	730	411	890	337	1050	286	1210	248	1370	219	1530	196
580	517	740	405	900	333	1060	283	1220	246	1380	217	1540	195
590	508	750	400	910	330	1070	280	1230	244	1390	216	1550	194
600	500	760	395	920	326	1080	278	1240	242	1400	214	1560	192
610	492	770	390	930	323	1090	275	1250	240	1410	213	1570	191
620	484	780	385	940	319	1100	273	1260	238	1420	211	1580	190
630	476	790	380	950	316	1110	270	1270	236	1430	210	1590	189
640	469	800	375	960	313	1120	268	1280	234	1440	208	1600	188
650	462	810	370	970	309	1130	265	1290	233	1450	207
660	455	820	366	980	306	1140	263	1300	231	1460	205
670	448	830	361	990	303	1150	261	1310	229	1470	204
680	441	840	357	1000	300	1160	259	1320	227	1480	203
690	435	850	353	1010	297	1170	256	1330	226	1490	201

Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres	Khz	Metres
540	555.2	700	428.3	860	348.6	1020	293.9	1180	254.1	1340	223.7	1500	199.9
550	545.1	710	422.3	870	344.6	1030	291.1	1190	251.9	1350	222.1	1510	198.6
560	535.4	720	416.4	880	340.7	1040	288.3	1200	249.9	1360	220.5	1520	197.3
570	526.0	730	410.7	890	336.9	1050	285.5	1210	247.8	1370	218.8	1530	196.0
580	516.9	740	405.2	900	333.1	1060	282.8	1220	245.8	1380	217.3	1540	194.7
590	508.2	750	399.8	910	329.5	1070	280.2	1230	243.8	1390	215.7	1550	193.4
600	499.7	760	394.5	920	325.9	1080	277.6	1240	241.8	1400	214.2	1560	192.2
610	491.5	770	389.4	930	322.4	1090	275.1	1250	239.9	1410	212.6	1570	191.0
620	483.6	780	384.4	940	319.0	1100	272.6	1260	238.0	1420	211.1	1580	189.8
630	475.9	790	379.5	950	315.6	1110	270.1	1270	236.1	1430	209.7	1590	188.6
640	468.5	800	374.8	960	312.3	1120	267.7	1280	234.2	1440	208.2	1600	187.4
650	461.3	810	370.1	970	309.1	1130	265.3	1290	232.4	1450	206.8
660	454.3	820	365.6	980	305.9	1140	263.0	1300	230.6	1460	205.4
670	447.5	830	361.2	990	302.8	1150	260.7	1310	228.9	1470	204.0
680	440.9	840	356.9	1000	299.8	1160	258.5	1320	227.1	1480	202.6
690	434.5	850	352.7	1010	296.9	1170	256.3	1330	225.4	1490	201.2

History

Radio waves, as they vibrate their way through the ether, can be identified either by their "wavelength", or their "frequency". (Wavelengths are measured as the distance between wave troughs, frequencies are measured by the number of vibrations that pass a point in a set period of time.)

Through the early nineteen-twenties, it was the standard practice internationally to classify transmissions by their wavelengths. Therefore, with the establishment of the broadcasting services in Australia, stations were initially assigned meters. Of course early Australia Radio's were "sealed set's".

These radio's were set to a single wavelength. Naturally, people with crystal sets or the enthusiasts were able to get around this with their home built equipment. 

For the rest of listeners it meant having multiple sets. 

Naturally, the system wasn't popular, sales of radios fell and the system was gone after 12 months.

The dials on the early Australian radios were marked in Metres, but this soon gave way to station markings.

However, Short Wave used, and still uses metres. Long Wave was never a thing in Australia.

Station markings continued until the very end of Australian manufacture in 1974. From then mostly Japanese radios were dominant and they of course used frequency markings.

Wavelength and Frequency

 Frequencies are measured in terms of the number of "cycles per second". This is why older radios with frquency markings have KC instead of Khz. In the case of AM broadcast stations, which use frequencies of hundreds of thousands of cycles per second, the prefix "kilo", is usually used. For FM it's "mega" or Mhz.

Conversion Charts

However, there is one area of inconsistency, measurement of the Speed of Light. Therefore I have  included two slightly different charts.

Since frequencies and wavelengths are mathematical reciprocals, all you need to do to convert from one to the other is to divide the value into the speed of light, as measured in kilometres per second. The two charts reflect the two terms: "rough value" versus "higher accuracy".

In the early 1920s, the best estimate for the speed of light was 299,820 kilometres per second. (This is actually a little high--the current accepted value is 299,792.458 kilometres per second). The was often rounded to an even 300,000, to make the calculations easier. Also, they just reported the result to the nearest whole metre. In contrast, the more precise people, using 299,820, generally carried the result to the nearest tenth of a metre. Thus, in the above charts, 560 kilohertz calculates to 536 metres using 300,000, while the more precise 299,820 calculation gives 535.4 meters. (Today, the actual answer is 535.343675 meters [calculated as 299,792.458 divided by 560])

Please keep in mind the United States uses 10 khz steps for frequency, however most of the remainder of the world uses 9 khz steps. The later allows a few more stations, but the radio needs to be more selective. Older radio designs tend to pick up ajacent stations. This is less of a problem now as AM is being phased out in favour of FM, DAB+, and the internet.