Local oscillator 8MHZ
Wanted frequency 144MHZ ---145MHZ
8 to 144 is x 18 so formula is as follows 144/18=8
145.000 = 8.055 145.025 = 8.056.94 145.050 = 8.058.3 145.075 = 8.059.72
145.100 = 8.061.1 145.125 = 8.062.5 145.150 = 8.063.8 145.175 = 8.065.27
145.200 = 8.066.6 145.225 = 8.068.05 145. 250 = 8.069.4 145.275 = 8.070.83
145.300 = 8.072.2 145.325 = 8.073.61 145.350 = 8.075 145.375 = 8.076.38
145.400 = 8.077.7 145.425 = 8.079.16 145.450 = 8.080.5 145.475 = 8.081.94
145.500 = 8.083.3 145.525 = 8.084.72 145.550 = 8.086.1 145.575 = 8.087.5
PYE CAMBRIDGE RECEIVE CRYSTALS for conversion to 145MHZ VHF
Example: The wanted receive frequency 145.500mhz minus the IF of 10.7mhz =134.3mhz
The 134.3mcs is divided into 3 which would mean that the receive crystal for 145.500mhz is 44.766mhz
The 44mhz range of crystals is used as a 3rd overtone device.
145.000 = 44.7666 145.025 = 44.775 145.050 = 44.7833 145.075 = 44.7916
145.100 = 44.8000 145.125 = 44.8083 145.150 = 44.8166 145.175 = 44.825
145.200 = 44.8333 145.225 = 44.8416 145.250 = 44.8500 145.275 = 44.8583
145.300 = 44.8666 145.325 = 44.875 145.350 = 44.8833 145.375 = 44.8916
The above crystal information is used when converting a Low-Band Cambridge AM 10 for two metres. Somewhere I have the spec for converting to FM I shall have a look shortly. I have a converted Cambridge and although I do not use it at the moment it is fully functional with 6 channels (25kcs apart) and works fine.
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Heatherlite Mobile Microphone
Microphone wiring colours for Heatherlite mobile microphone when used with Yaesu ft290 mk 1.
Yellow--mic o/p Red--ptt White--up Blue--down and don't forget the braid as ground.
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Some of my Valve (Tube) collection
3A4-----12Q7GT-----GSN7GT-----6QS7-----EF36-----U74-----7C5-----PL33-----12SG7
OZ4-----JRC-6C4-----7D8-----N77-----7S7-----JNU-IS4-----6K7GT-----KT66-----JRC6C6
Z77-----6SQ7-----X78-----12AU7-----6F1-----12AT6-----SP61-----6C4-----D1-----EBC33
ECH81-----ECH81-----6AL5-----7D9-----EZ81-----EF92------EA50-----PY83-----1G6GT/G
7Y4-----8F14-----EF184-----EF86-----ECL305-----ECC82-----6F29-----6F28-----ECC804
12AH7GT-----6C4-----6A8G-----6K8G-----6SH7-----2H6-----DK96-----UCC85-----X18
ECC85-----9D6-----6AT6-----3Q4-----PCF82-----N329-----ZD17-----W17/IT4-----N309
The list above is a random selection of about 120 valves drawn from my big archive valve collection..
For a quick summary click on http://en.wikipedia.org/wiki/KT66
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A Pokey back yard
Due to my restricted location and my small back yard in a ground floor apartment hf aerials have always a bit of a problem and normally I have had to modify them to fit, which is normally a compromise and I am sure that with the modifications performance has suffered. The flat above me has always had a good view of them but nobody has ever complained "my neighbours have always been absolute diamonds" and some of my contraptions they could touch by reaching over from their balcony, that's how close the aerials were and one still is at the moment.
Following aerial formula is the way to do things but 9/10 times you come up against a brick wall "literately" and a tweak or two here 'n' there will make do. I have never used a automatic aerial tuner (ATU) and my old Italian 1KW ATU has always been able to tune anything, or more or less anything.
In the past I managed to receive and transmit on the aluminium building trim that runs the length of my block (300ft) I removed a joining piece within my plot more a less centre and was left with a lengthy horizontal dipole. I attached a transmission line and messed about with it for a week. Using only low power (10w) I had no interference complaints and worked two stations on 80m and heard a lot more. I
As it is now
Thirty foot to the top of the inverted V, not really a inverted V in the true sense, because of the restrictions of my garden about ten feet of the end of each wire leg, runs through a eyelet and then drops vertical and is weighted by a automatic tensioner on each leg.
OK I'll come clean, not fully automatic but semi-automatic.
It works like this.....on each leg I attach one plastic 300ml drinks bottle, the type that has a pull out stopper arrangement After pulling out the stopper so it clicks open drill a hole through it big to attach the aerial wire. Pour some water in the bottle ( this will vary with your wire gauge ) to about a third full and just let it hang through your eyelet arrangement. My vertical eyelet arrangement is a couple of vertical bamboo poles one for each leg with a car exhaust rubber pinched tight against the pole using big chunky cable tie ( UV protected ). Drop the cables through the centre of the rubber eyelet and fix to the drinks bottles, I have discovered through the medium of time that water runs down the aerial legs and the bottles fill up with water as bad weather progresses this extra weight is beneficial to steadying the fibre glass pole and saving the aerial in the accompanying winds because there is no fixed wire ends to snap loose. I cannot say this would be good for all types of wire but I do know because of the three years since mine was first erected it works perfectly with my good quality G5RV and a 300ml drinks bottle. Even with the bottles full it does not seem to stress the aerial. In the three years the rubbers have not worn and the cable ties have not perished.
PS after the rain just squeeze the surplus out, or keep it full for the windy winter months.
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