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Old 4th Mar 2016, 8:12 am   #141
stevehertz
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

Will do, thanks Gary. Trouble is, access to back of this big heavy set sitting on a shelf is not easy and the aerial termination is screwed, so I have to get a stubby screwdriver between the back of the set and the wall as I perch on a plastic step thingy trying to peer over the back with my mirror on a stick in one hand, screwdriver in the other and my stomach pushed agains the set in case it should come too far forwards and crash down on to my toes! I'm sure you didn't need that graphic explanation, but it is difficult to keep accessing the back (or guts) of the set once it is place. But need is must.... !

I'm beginning to think mind that the reading 4.5 is kinda ubiquitous - especially in the light of the Sony that you have - as the manual explains how to input a signal at 98Mhz of a certain magnitude and twiddle a pot until the meter reads - you guessed it - 4.5. I suppose I could mark the position of that pot and try twiddling it under different signal strengths and see what happens?
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Old 30th Mar 2016, 7:08 pm   #142
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

I'm loving using this receiver now. Just one thing, there's only one AUX input and I'm using that for my CD player. I want to connect a DAB tuner to the Sony to augment the FM and AM radio that it already has, so I need another line level input. However, the receiver does have two phono inputs and I'm only using one. How easy/difficult would it be to 'bypass' the phono EQ stage of say 'Phono 2' and use it as a line level input? Note, I realise that I could use a line level switching box outside the receiver to switch between the CD player and the DAB, but I don't want to go down this route.
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Old 30th Mar 2016, 8:27 pm   #143
Edward Huggins
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

What about using the "TAPE" switched line-in socket? Or, you could maybe use a L-PAD attenuator if you want use the PHONO 2. Whilst this might affect the frequency response, it is probably going to be no worse that the terrible compression on most DAB transmissions anyway. If I were you, I would use a good quality "lossless" line-level switch box. You could cetainly find youself with more complexity and possible signal loss if you start digging around in the post-RIAA stage on the Sony circuit board! Edward
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Old 31st Mar 2016, 6:55 am   #144
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

Both tape inputs will be in use by cassette and reel to reel machines, so they can't be used. Allowing the frequency response curve of a phono RIAA correction filter to affect an attenuated line level signal is a no-no, that is just plain wrong, never mind getting into the quality of DAB transmissions, they're not half as bad as people make out subjectively, but in any case, two 'bads' don't make a 'good'. Re a switch box, I've already said I don't want to use one.
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Old 31st Mar 2016, 1:28 pm   #145
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

I had this quandary a couple of decades ago with a Rotel receiver with 2x phono inputs, as there was only one phono pre-amp board whose inputs were selected by the main input selector, this selector also having two ways per channel parallelled for the phono-amp output into the pre-amp section with the other line-level sources, it was an electrically simple, if mechanically fiddly job to just transfer the connections from the second phono input sockets to the "line" switch wafer, breaking the original parallel link with phono position 1. The remaining first phono input socketry was similarly simply directly linked to the phono-amp input, now avoiding the switching altogether and notably reducing background hum as it avoided the nest of wiring around the selector switch, which included LVAC for source selector lamps....

Hopefully, the Sony uses some similar switching, though I know that some Japanese manufacturers were more production-sophisticated than others with PCB switch banks that would be less amenable to simple alteration than hard-wiring.
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Old 31st Mar 2016, 1:45 pm   #146
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

I managed to do this successfully with a Leak Delta 70, converting one of the "disc" (i.e. magnetic cartridge) inputs to line-level to accept the output from a CD player, but as turretslug implies, it all depends on how the manufacturers have designed the switching.
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Old 31st Mar 2016, 5:56 pm   #147
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Default Re: Sony STR-6800 receiver - stiff tuning, dial lamps and...

Ok thanks guys. Clearly I need to look at the circuit, it may just be a case of swapping some wires over as described.
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