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Retune 21-3-18 (Rowridge) - lost Com 8 (Resolved)

prpr said:
...your aerial/downlead/rx infrastructure is in need of attention.
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I'd agree something could be improved.

I've just run a check on the signal levels here in Guildford from Crystal Palace using an Antiference XG9BK (combined Group A & B/470-734MHz), a 15dB amp left over from analogue days when it was needed for Channel Five, an 8-way Global Loftbox and all cabling in CF100/PF100 and F connectors. Measured on an HDR-T2.

Channel__ERP_____Level
22________200kW__87%
23________200kW__85%
25________200kW__89%
26________200kW__88%
28________200kW__90%
30________200kW__90%
55________43kW___75% (743.25MHz)
56________40kW___75% (751.25MHz)

Pretty much what I'd expect, bearing in mind the reduced power levels of CH55 & 56 and their being above the aerial's working range.
Plugging in a 10dB attenuator drops these figures by 9-10% so 10% = 10dB on the HDR.

(Apologies if my table formatting workaround doesn't work once posted.) Looks like it's OK.
 
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prpr said:
Have you still got COM8? If you have, then something weird is happening. If not, then your aerial/downlead/rx infrastructure is in need of attention.
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No I don't have Com7 or Com8 - I had originally only checked some Com7 channels.
The digital.uk page does indicate I might need an aerial upgrade to receive them now :( Isn't progress wonderful

I was rather confused by the Mux info on the Webif diag pages which while it shows the correct channel numbers bears no relationship to the current signal strengths for Com7/8.
Presumably this is a snapshot taken in the dim and distant past when I last did a full retune and all the muxes were on receivable channels.
With tunefix-update removing the need for retunes is there a way of getting up to date signal information in the webif?
(not sure why com7 show as unknown)

1-Fullscreen capture 02052018 192543.jpg1-Fullscreen capture 02052018 192543.jpg
 
Black Hole said:
No. We are in the hands of the stats gathered by the OEM code at the time of a retune.
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But a lot of what was thought impossible has proven possible over the years.

The real time data must be accessible since the sui can display it varying - it would just require @af123 ploughing through the source code which he might not have the time or inclination to do!
 
MymsMan said:
I was rather confused by the Mux info on the Webif diag pages which while it shows the correct channel numbers bears no relationship to the current signal strengths for Com7/8.
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That raises an interesting point. Should tunefix-update kill the existing figures when it moves a mux. to a different RF channel?
I'm thinking it probably should, to save confusion.
With tunefix-update removing the need for retunes is there a way of getting up to date signal information in the webif?
Click to expand...
The only way I can think of is to manipulate the database manually, with the Humax software not running. Or do a retune.
(not sure why com7 show as unknown)
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Presumably you don't have BBC News HD. Or your WebIf is ancient.
 
prpr said:
That raises an interesting point. Should tunefix-update kill the existing figures when it moves a mux. to a different RF channel?
I'm thinking it probably should, to save confusion.
Click to expand...
I'd say it should - the data is simply not applicable, even if the numbers happen to be the same.
 
prpr said:
I'd take that out if I were you. Certainly not needed on your installation.
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Easy enough to remove as it's inside the loft, but as theres's what looks to be at least 10dB of headroom and no overloading problems it's been left in.
 
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