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Good luck with your own Projects, John - and thanks for this input - I was cogitating on that same RLY2. I have been mapping the route in two directions - (1) Analog from VAUXL&R to IC801 and (2) Backwards from the SPKR FL & FR through that RLY2 on page108/D2 back to the IC801pin21&23 and was just on the point of wondering how the signals got through IC801 from pin84(VAUX_L) and pin83(VAUX_R) to pins 21&23 (FLOUT)&(FROUT)? Could be internal switching.
In the meantime my Son Maxim is here from Guildhall University as he's going to play Violin in a gig in the country. It was Maxim who set up the AVR to our T/V and got that Test Wizard to show itself. Michael Studio1 UK
Thanks, John. Looking at the Cct.Diag. Page108/D2 - it seems that this RLY's contacts are 'normally open' - to give it in the telephone vernacular of the telephone engineer - which I was, with BCTel in Vancouver many years ago. The relay's coil is actuated by 'FV' Cct. by Q2,Q9,D2 from [FRL]> which starts at CP12 pin10 - otherwise known as (RELAY_F) page108/A9. So it seems I should solder a Test-tail to the coil of RLY2, re-assemble the AVR and test for Voltage as the AVR powers on. At the same time I must add Test-tails to CN1 pin1(FL)& pin2(FR) Page108/A3 = Page106/O3 pin1(FL)& pin2(FR) to see if the signal tones have got this far - maybe I should do that first. Michael Studio1 UK 17:14BST 26-05-2018
Good place to look-see if FRL is high in order to switch on FV and in turn relay.
Ahh, that's how you have an electrical/electronic aptitude.
Beautiful city that Vancouver, BC.
It was in 1960. Power on the AVR. RLY2 coil Voltage = 13V - across the coil. Signal Tones arriving (they weren't at first, so I powered down the AVR and powered it up again) Yes! at IC30 pins 1&2 page126/B5. No tones at FL CN1pin1 or FR CN1pin2 page108/A3 = page106/O3. My Audio Amp. reference for Tones is Chassis GND. I need to fire up the endoscope so I can see to 'sound-probe' the IC801 Page114 at pin83(VAUX_R) and pin84(VAUX_L) This is where these tones make their first entry to IC801 - and I'm curious to see where they come out - it should be pin54 (A/D_L) and pin55 (A/D_R) enroute to IC30. We'll see - and I'll post back. Michael Studio1 UK 08:08BST 28-05-2018.
So I have continued in the Lab: - Revelations here:
Get back to your Cct.Diags. and follow the Analog route from VAUXL & VAUXR to IC801 and Beyond . . . . .
Analog route from VAUXL&R - Page130/O3 -> IC101/2 -> CP/CN pins3&5 -> CX4 pins8&6
Page130/A5 -> Page129/N6 -> CN2/H3 pins6&4 -> Page112/J3 -> CP114 pins18&17 ->
Page114/J1 -> CN114 pins18/17 -> IC801 pin84 (VAUX_L) & pin83 (VAUX_R) -> pin54 (AD_L)
Pin55 (AD_R) NOTE changing the SOURCE SELECT knob causes the tone to disappear.
The IC801 is therefore an Analog Switcher. I have checked this by injecting the two Signal
Tones into ‘CD’ phono jacks, changing the SOURCE SELECT to ‘CD’ and the tones appear at
IC801 pin54 (AD_L) & pin 55 (AD_R). So that solved that mystery. Continue:[AD_L]> and [AD-R]> ->
page114/F1 -> CN115 pin17 (A/D_L) & pin15 (A/D_R) -> page112/L9 -> CP115 pin17 (A/D_L)
& pin15 (A/D_R) -> CP11 pin32 (ADINL) & pin30 (ADINR) -> page129/H5 CN2 pin32 (ADINL)
& pin30 (ADINR) -> page126/N2 -> [ADINL]> & [ADINR]> -> IC30 page126/B5 pin1(AINR) &
pin2(AINL). where both Signal Tones appear.
I have yet to check continuity through RLY2 - so with 'Tails' attached to CN1 - page108/A3 - pins1(FL)&2(FR) and with access to Jack1 - (FLA) & (FRA) there seems to be no reason I cannot use a DVM between these two points. Continuity confirmed. Furthermore, turning Off the AVR with this Test set up results in an Open Cct. on both FL and FR through RLY2. Ergo RLY2 is operating properly. Michael Studio1 UK 11:11BST 28-05-2018
Get back to your Cct.Diags. and follow the Analog route from VAUXL & VAUXR to IC801 and Beyond . . . . .
Analog route from VAUXL&R - Page130/O3 -> IC101/2 -> CP/CN pins3&5 -> CX4 pins8&6
Page130/A5 -> Page129/N6 -> CN2/H3 pins6&4 -> Page112/J3 -> CP114 pins18&17 ->
Page114/J1 -> CN114 pins18/17 -> IC801 pin84 (VAUX_L) & pin83 (VAUX_R) -> pin54 (AD_L)
Pin55 (AD_R) NOTE changing the SOURCE SELECT knob causes the tone to disappear.
The IC801 is therefore an Analog Switcher. I have checked this by injecting the two Signal
Tones into ‘CD’ phono jacks, changing the SOURCE SELECT to ‘CD’ and the tones appear at
IC801 pin54 (AD_L) & pin 55 (AD_R). So that solved that mystery. Continue:[AD_L]> and [AD-R]> ->
page114/F1 -> CN115 pin17 (A/D_L) & pin15 (A/D_R) -> page112/L9 -> CP115 pin17 (A/D_L)
& pin15 (A/D_R) -> CP11 pin32 (ADINL) & pin30 (ADINR) -> page129/H5 CN2 pin32 (ADINL)
& pin30 (ADINR) -> page126/N2 -> [ADINL]> & [ADINR]> -> IC30 page126/B5 pin1(AINR) &
pin2(AINL). where both Signal Tones appear.
I have yet to check continuity through RLY2 - so with 'Tails' attached to CN1 - page108/A3 - pins1(FL)&2(FR) and with access to Jack1 - (FLA) & (FRA) there seems to be no reason I cannot use a DVM between these two points. Continuity confirmed. Furthermore, turning Off the AVR with this Test set up results in an Open Cct. on both FL and FR through RLY2. Ergo RLY2 is operating properly. Michael Studio1 UK 11:11BST 28-05-2018
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Hello Dries - Are you suggesting the outputs are sensitive to the presence of a Speaker - and will not turn on unless a speaker is present? There's nothing in the SPKR_B'D Circuitry to suggest that. In fact one of the prerequisites for the ADJUSTMENT to the AudioSection on page56 is that there shall be no load - do not connect speaker, dummy resistor etc. A good thought though with this strange beast! When I first turned the AVR on today, with test tones in to VAUXL&R, these tones were not being 'seen' at IC30. They only got as far as the HDMI connector of the ffc ribbon (CX4). I turned the AVR off and on a couple of times and the tones then got through to IC30. Strange. I didn't 'do' anything - jiggle connectors or move the 'stack' of pcb's. It just . . . 'happened' Michael Studio1 UK
BTW - I do not have anything connected to the SPKR Terminals. Michael.
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Great job Michael, you seem to be narrowing in on things. Encouraging news that relay 2 is working and ic801 sequencer appears to be working. Tomorrow, I'll try and cross ref your list of findings to see if I can help.
If we run out of ideas I'd be tempted to jumper through some of the circuitry (with extreme caution) to see if your amp section is working. But I'd hold off on that for now.
Regards, John
If we run out of ideas I'd be tempted to jumper through some of the circuitry (with extreme caution) to see if your amp section is working. But I'd hold off on that for now.
Regards, John
First I will check that all IC's in the digital path are getting power - at least we'll know that isn't the problem. But I recall that business on page117/J7 - TR16 & TR17. Is the fact that there's a Voltage reading Page129/M4 CN5 pin18 (SWM5V) = 5.2V. & pin17 (SWM3.3V) = 3.3V. indicative that 'all is OK' there? I have added a 'Test Tail' to CN13A pin 10 (DA+5V.) on the SIDE_CONNECTOR page111., since almost every time I turn the AVR 'ON' the Signal Tones are not getting past the CX4 ribbon cable entrance to the HDMI_B'D. And I have found: CN13A pin10 (DA+5V.) is only reading +1.52V. with reference to DGND - and therefore not firing the IC's in its domain. Michael Studio1 UK 14:28BST 29-05-2018
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Good plan.
Check for DA+5v with Agnd as reference.
If still only1.5v check ic105 on p110.
So the problem IS with the SWM3.3V supply - and I cannot fathom it - the 3.3V. seems to spring from nowhere - trouble is, it's stopped springing in sufficient Voltage to operate IC30 - and presumably all IC's powered by it. Until this loss of 3.3V. is rectified I can get no further. Yesterday the 3.3V. was intermittent. Today it has gone. HELP!! Michael Studio1 UK 20:06BST 29-05-2018
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Thanks, John. Checked at CP13A = +5.11V. Michael
Checked SWM3.3V. at CP5 pin17 = 3.1V. ref. DGND
IC30 pin7 = 1.52V. ref DGND
CX4 (ribbon) pin3 = 4.55V. !! ref: DGND Michael
IC30 pin7 = 1.52V. ref DGND
CX4 (ribbon) pin3 = 4.55V. !! ref: DGND Michael
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Ic30 5v supply is referenced to DAgnd, not Dgnd.
Dgnd has a bank of capacitors between it and DAgnd. Look into how the grounds converge.
PS: please note what page you're on so I don't have to hunt for it.
Dgnd has a bank of capacitors between it and DAgnd. Look into how the grounds converge.
PS: please note what page you're on so I don't have to hunt for it.
What a pain, trying to trace from page to page. Wish it was one huge page.
Anyway, I'm trying to track down DAGND.
It goes to CP115 pin 5,8,11,14 and also to CP11 (on page 112.) pins 15,17,21,23 etc.
It looks like AGND and DACRTGND all merge together with DAGND here on CP11.
Edit: Just Agnd and DAgnd come together there. I'd put my positive lead on DA+5v and try and probe around the grounds to find out where it's comming from.
Anyway, I'm trying to track down DAGND.
It goes to CP115 pin 5,8,11,14 and also to CP11 (on page 112.) pins 15,17,21,23 etc.
It looks like AGND and DACRTGND all merge together with DAGND here on CP11.
Edit: Just Agnd and DAgnd come together there. I'd put my positive lead on DA+5v and try and probe around the grounds to find out where it's comming from.
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So you do have DA+5v with respect to Agnd?
You should have the same voltage wither using Agnd or DAgnd as a ref.
Ah! DA-GND - I will retest - AND quote the page! Apologies - I thought I had learned that! Now I must find DA-GND. Using 'CNTRL + F' on the DELL with the Service Manual I get the 'Find' box. Page 112/L3 CN11 pins17 to 33 (all odd pins) as: DAGND. I have attached a Test Tail to DAGND CN11 pin33 page 112/L3 and taken a DC reading at IC30 pin7 page 126/B5 = 1.5V ref. DAGND. Then to Page110/B4 CN13A pin7 = +8.1V ref AGND pin4 CN13A pin6 = -7.8V. ref AGND pin4. THEN: CN13A pin10 = +5.1V ref AGND pin4. Michael Studio1 UK 07:39BST
Thanks, John. In the words of Prince Harry and Meghan on Saturday: "I do". I get +5.1V. ref AGND on CN13A Page110/B4 Michael
Agreed about "What a pain, trying to trace from page to page. Wish it was one huge page." My short term memory isn't all that it could be and dodging about from page to page . . by the time I've found the page I've forgotten what I'm looking for! Anyway, I did track down DAGND as you mentioned above - along with the GND merger on CP11 page112/K3. But, more to the point, page 110/E3 shows IC105 referencing DA_+5V. to AGND - so my guess is that's pretty conclusive. But where has the Voltage for IC30 gone? Michael Studio1 UK 09:56BST
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