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Signal dropouts (signal strength 30% - is this too low?)

Black Hole said:
I'm not, that's for sure.
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I know. That's why I said 'we' reather than we.
Re transponder. Being from an air traffic/air defence radar background, Of course I 100% agree with you, but for some obscure reason a 're-transmitting multiplex' from a TV satellite is called a 'transponder'. I suspect that this has been derived from early communication sats, but quite why, I don't know.
 
OK so it does rather look like something dodgy with the tuner component on the Humax. I just plugged in the dusty old box from the loft and it's showing 73% signal strength from the same aerial. Now I need to rediscover whether it really was the fan that caused its banishment to the loft, or something else...
In the meantime if I migrate the HDD from the other box will I be able to restore my recording schedule from the HDD, or are the backups stored in NVR??
tom's humax signal strength.jpg
 
Ian Manning said:
OK so it does rather look like something dodgy with the tuner component on the Humax. I just plugged in the dusty old box from the loft and it's showing 73% signal strength from the same aerial.
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Fits with my diagnosis, assuming both HDRs are tuned the same - I've not checked back through the thread.
 
Ian Manning said:
OK so it does rather look like something dodgy with the tuner component on the Humax.
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Oh dear, I guess I lost. At least that means you don't need to spend money on aerial men.

If both your units are pre-RE models, I reckon the tuner cans are transplantable. That will be easier than repairing a motherboard fan fault (unless it's something obvious like a dry joint or broken track).

Ian Manning said:
In the meantime if I migrate the HDD from the other box will I be able to restore my recording schedule from the HDD
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Yes, with usual comments about encryption etc - if you have routinely decrypted you'll be OK.
Ian Manning said:
or are the backups stored in NVR??
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No
 
Would you happen to know if the transplanting the tuner would involve any soldering?
I noticed that the box in the loft has a slightly different rear panel - the RF sockets are aligned horizontally rather than vertically (i.e. the RF out is to the right of the RF in). In the "current" box they are vertically aligned - with the RF in on top. Does this give any clue as to which model is newer?
Thanks for confirming re. schedule backups. I've kicked off the mass decryption process.
 
Black Hole said:
Oh dear, I guess I lost. At least that means you don't need to spend money on aerial men.
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Happens to us all once in a while.
Black Hole said:
If both your units are pre-RE models, I reckon the tuner cans are transplantable. That will be easier than repairing a motherboard fan fault (unless it's something obvious like a dry joint or broken track).
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Shouldn't be any different with the V2 single tuner module one, although I've not got one apart in front of me. With the V1 twin tuner one it I'd put money on the first tuner module being the suspect one.

Musing on what might have happened, other than a mechanical fault with the RF In connector, one possibility is a nearby lightning strike taking out the first module's RF stage. Had that happen here with the Loftbox - years ago the VHF input went low gain after a thunderstorm but the UHF one and everything else was fine. Global replaced it under warranty and I now have a spare just in case.
 
Ian Manning said:
Would you happen to know if the transplanting the tuner would involve any soldering?
I noticed that the box in the loft has a slightly different rear panel - the RF sockets are aligned horizontally rather than vertically (i.e. the RF out is to the right of the RF in). In the "current" box they are vertically aligned - with the RF in on top. Does this give any clue as to which model is newer?
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Ah, in that case swapping tuners is off. The earlier one with the horizontal RF connections uses two tuner modules, the later one with them vertical has a single module and seems to be rather rare. And yes, soldering is required.
 
everthewatcher said:
Ah, in that case swapping tuners is off. The earlier one with the horizontal RF connections uses two tuner modules, the later one with them vertical has a single module and seems to be rather rare. And yes, soldering is required.
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Thanks for confirming - that's one less decision to make. So any views re. the relative merits of the two models - any reason to rate one more highly than the other? Just asking in case I need to look at doing a hardware repair,
 
Ian Manning said:
Thanks for confirming - that's one less decision to make. So any views re. the relative merits of the two models - any reason to rate one more highly than the other? Just asking in case I need to look at doing a hardware repair,
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Got one of each here. The first was a nearly new V2 (or REV) from eBay that was no longer wanted after being 'fixed' under warranty (from the included paperwork it just needed a firmware update) and has been the main machine for the six years since then. The second was a V1 donated to a charity shop I did work for that turned out to have a broken PSU PCB (documented here somewhere). Fixed it and it's been the so-far unneeded spare.
 
Ian Manning said:
In the "current" box they are vertically aligned - with the RF in on top. Does this give any clue as to which model is newer?
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That's what we refer to as "RE", and we believe was manufactured towards the end of production when they couldn't source the original tuner any more and had to re-jig.

everthewatcher said:
Musing on what might have happened, other than a mechanical fault with the RF In connector, one possibility is a nearby lightning strike taking out the first module's RF stage.
Click to expand...
I still find this very odd, although the RE hardware might have a bearing on it. If the fault is on the RF input, why would the HDR-FOX have any reception at all? If the fault is a degradation rather than a total loss, why is there no pass-through signal at all?
If the fault is on the pass-through, why is there a degradation to the HDR-FOX's signal? None of this adds up to me, other than to consign it as a mystery of RF.
 
Black Hole said:
That's what we refer to as "RE", and we believe was manufactured towards the end of production when they couldn't source the original tuner any more and had to re-jig.
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There are more changes than that. The PSU is different and only supplies 12V to the main board for a start.
 
Black Hole said:
I still find this very odd, although the RE hardware might have a bearing on it. If the fault is on the RF input, why would the HDR-FOX have any reception at all? If the fault is a degradation rather than a total loss, why is there no pass-through signal at all?
If the fault is on the pass-through, why is there a degradation to the HDR-FOX's signal? None of this adds up to me, other than to consign it as a mystery of RF.
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OK. As the passthrough needs power to work it seems reasonable to assume there's an active component of some kind in the RF In/Out path and it's not a simple link. I've not got a note of the tuner part number so can't look it up and the manual doesn't give info about any gain between RF In and Out but it could be there's a low-gain RF or band switching stage and the RF Out is fed from after it.

As for the HDR working at all, using a 10dB attenuator here the reported signal strength drops from 88% to 77% so over that range 10% ≈ 10dB. If this is the same over the whole range a drop from 75% to 30% would be 45dB but the HDR still works, just. So it's entirely possible a blown RF stage will still pass enough signal through strays.
 
So you are postulating two faults not one. I start from the premise there is one fault to explain all the symptoms, it is unusual for there to be two independent faults (unless perhaps the pass-through fault has been there for a long time).
 
This is getting tedious. Even a trickle on the RF Out should register with the TV. That's the last I'm saying on the matter.
 
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