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I have just successfully repaired one of these. It was stuck in standby.
The problem is not the PSU board as commonly supposed, but the 10 x 220uF 16V through-hole capacitors on the mainboard. These are the notoriously unreliable Sam Young type which seem to last only until the end of the warranty. All 10 were significantly out of specification.
On this model, and several others in the Humax line-up, the main PSU (internal or external) only supplies 12V. The other required voltages are generated on the mainboard
Ah, you don’t lose the old skills Andy!
Les
Interesting. I have a couple of ‘please wait’ DTR-T1000s which I bought cheaply for spares. By swapping around components, I thought that the problem was on the main board, but didn’t know what I could do to fix it. Out of interest, I have ordered some new caps and I will replace the Samyoung ones on the board of one of the units to see if that fixes it. I ordered Rubycon ZLH series capacitors (rated for 6000h at 105°C): did I make a good choice?
The HDR-FOX T2 (revised edition) also uses the same 12V only PSU, but is generally a much more reliable unit than the DTR-T1000. I do have one of these which is not in use, because it tends to freeze when it comes out of standby. I know it is a problem related to the main board. This unit also has the same Samyoung capacitors, but only five, not ten, of them. I am tempted to replace these too to see what happens.
MontysEvilTwin I ordered Rubycon ZLH series capacitors (rated for 6000h at 105°C): did I make a good choice?
I used Rubycon YXF ones, but I’m sure that the ZLH range will work just as well. I’m ordering some Panasonic FR ones for any future repairs or kits.
andyfras – 1 hour ago »
MontysEvilTwin I ordered Rubycon ZLH series capacitors (rated for 6000h at 105°C): did I make a good choice?
I used Rubycon YXF ones, but I’m sure that the ZLH range will work just as well. I’m ordering some Panasonic FR ones for any future repairs or kits.
Not being an expert it is hard to know what to pick. I know that Rubycon is a generally regarded as a good brand: I get the impression that it is best to use Japanese components, like Rubycon, Nichicon and Panasonic. On the Farnell website there were eight different series to choose from (Rubycon, 220μF, 16V). A couple were a lot more expensive (probably for higher end audio products) and a couple were cheap, but were only rated at 2000h/ 105°C. This left about four caps of similar spec. and price. I guess that the differences between these are quite subtle.
Any Chance of a location picture if it is just a soldering iron fix ?
Something I would like to add to my repair file
I’ve marked the capacitors with asterisks. The photo resolution is not great due to the forum size limit.
[attachment=46506,624]
I tried this fix for mine although my one has slightly different symptoms. I get no light on the front of the box, only the ethernet port lights come on. All the capacitors that I switched out were within 10% of what they should be and there seems to be a steady 12v coming from the power supply. I did get it to turn on once afterwards but when I put it back into energy saver mode it failed again. Anyone got any other suggestions?
When you say that the capacitors you removed were within 10%, presumably you mean of their rated capacitance? The key measurement is ESR (Equivalent Series Resistance) which requires a specialist meter.
On the one I repaired, I did notice that one of the 10uF surface mount capacitors, bottom left of the picture above, was also out of specification, but I didn’t think that was the cause of the problem (I changed it anyway).
What capacitors did you use? They need to be low ESR versions, so ones from Maplin for instance are probably not good enough.
I used these: Panasonic EEU-FR1C221
You can’t get much better than the FR range.
As you can see above, I used Rubycon YXF capacitors which I happened to have in stock. I suspect that these are not quite as low ESR as the FR range, so I’m wondering if the total inrush current is too much for the TPS65251 power controller on the mainboard (as it was when I tried using 330uF FRs initially).
I don’t regret switching out those 10 capacitors, when it did turn on that one time the machine seemed a lot more responsive, it had been getting annoyingly laggy prior to failure. I’ve ordered myself an ESR meter now so I’ll have a poke around with that and see what I find.
Thanks Andy,
I just revived my ex-trial box (replaced once under warranty in 2013).
With help from an old solderer with professional tools and skill to remove old caps, box now revived. I used Rubycon 16YXF220MY0811 cpc order code CA00167.
I used a microscope to check when solder new, I only soldered from bottom, not sure if supposed to solder from top as well, not all holes fully soldered. NB not all caps have polarity marked on board – take photos before to refer to.
I’m not sure domestic tools would be good enough to remove old caps – but if you try there is the optional destructive technique pliers/mole grips to crush cans and then solder to old legs!
The old caps were all +10% on capacitance 240-250uF, new ones all -5% 210-215uF. They are supposed to be +/- 20% spec. I didn’t manage to locate a good ESR meter, but on one bridge old caps all 2-4 times (0.8-1.6 ohms) more than new (0.4 ohms). Most telling probably was that a component tester initially recognized one of the caps as a resistor not a capacitor.
Box still needed a visit to maintenance mode to reset firmware but no recordings lost. http://videos.youview.com/support/maintenance_mode.pdf Before cap change usually couldn’t get anything on screen, occasionally first boot screen but I’m sure no buttons ever worked….
You can tell the polarity from the board even if there is no '+' marked by one of the holes. The footprint of capacitor is enclosed in a white circle with a bump protruding around one of the holes. The hole inside the extra bump is for the negative leg of the capacitor (see photo).
I found an easy way to desolder and remove the old capacitors using a plastic cable tie. If you loop the tie around one of the legs on the top of the board (no need to actually fasten the tie) and pull it taut holding both ends, and then heat the solder with a iron from the underside. When the solder melts, pull on the tie and the leg will come free of the board from the top. If you then heat the solder fixing the other leg to the board, when it melts you can remove the capacitor by pulling on the body of the capacitor.
[attachment=47660,635]
I put plenty of fresh solder on each joint, then use a penknife to straighten the leads while melting the solder. While touching the tip of the iron across both legs, pull out the capacitor. Then use a desolder tool or braid to clear the holes.
I’ve just repaired another DTR-T1000 today. 8 out of the 10 Sam Young capacitors were about 4x the specified ESR. I used the Panasonic FR range capacitors. I found that the capacitors needed to be removed for an accurate ESR reading, as several capacitors have others in parallel when measuring in-circuit.
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