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SiriusHardware · 4th Dec 2018, 1:17 am

You seem to have got it quite well balanced. Unfortunately it's hard to say whether the figures are reasonable or not in terms of overall sensitivity because the generator doesn't seem to be able to put out precisely measured amounts of RF signal. Because of this, you can only really use it to make relative / comparative measurements rather than absolute measurements.

For example, connect the generator to the 777 which I assume you think is working well. Try generating a signal in the middle of the middle band on the 777 and then turn the generator output down, down, until the 777 is indicating exactly S1.

Then, without changing the output level or frequency, connect the generator to the Colt. Can the Colt 'hear' the signal as well as the 777 could? Ideally, it should indicate S1 as well, but there are possible variables - the S meter on the Colt may very well be adjusted differently for a start, so the actual sensitivity could be near-identical, but one meter might be adjusted to read higher than the other. On the other hand, if the Colt just doesn't hear the signal at all then it is still more deaf than your 'gold standard' radio.

When tuning the receiver, did you adjust anything other than T9-T10-T11?

4th Dec 2018, 1:17 am	#142
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,556	Re: Cybernet PTBM121D4X problems You seem to have got it quite well balanced. Unfortunately it's hard to say whether the figures are reasonable or not in terms of overall sensitivity because the generator doesn't seem to be able to put out precisely measured amounts of RF signal. Because of this, you can only really use it to make relative / comparative measurements rather than absolute measurements. For example, connect the generator to the 777 which I assume you think is working well. Try generating a signal in the middle of the middle band on the 777 and then turn the generator output down, down, until the 777 is indicating exactly S1. Then, without changing the output level or frequency, connect the generator to the Colt. Can the Colt 'hear' the signal as well as the 777 could? Ideally, it should indicate S1 as well, but there are possible variables - the S meter on the Colt may very well be adjusted differently for a start, so the actual sensitivity could be near-identical, but one meter might be adjusted to read higher than the other. On the other hand, if the Colt just doesn't hear the signal at all then it is still more deaf than your 'gold standard' radio. When tuning the receiver, did you adjust anything other than T9-T10-T11?