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| uk.tech.digital-tv (Digital TV - General) (uk.tech.digital-tv) Discussion of all matters technical in origin related to the reception of digital television transmissions, be they via satellite, terrestrial or cable. Advertising is forbidden, with no exceptions. |
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#1
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Having turned out not to have been affected by the end of InView EPG
service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. |
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#2
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ian field wrote:
Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. -- Tony |
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#3
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"Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. |
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#4
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ian field wrote:
"Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? -- Tony |
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#5
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"Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? The PSU was working (sort of) but the voltages were all high except the 3.3V and it probably had too much HF ripple upsetting the logic board. I was lucky the overal deterioration of the electrolytics caused symptoms I couldn't ignore. There's a couple of small electrolytics on the primary side that can cause gradual regulation failure as the ESR increases - capacitors with high ESR get a degree of self heating from the ripple current, if allowed to cool the ESR increases a lot with the result that the PSU can go bang if the mains goes off for a while and comes back on. One of these critical electrolytics is only 1uF - not hard to find a non-electrolytic replacement small enough to fit. If your's is anywhere near 10 years or more old, I'd reccomend a recap before it does go bang. Use the best high temp - low ESR electrolytics you can get hold of. I got 10uF multilayer ceramic chip capacitors to pad the 6 secondary side smoothers from a scrap LCD TV, but you should be able to order similar from the likes of Farnell. |
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#6
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ian field wrote:
"Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? The PSU was working (sort of) but the voltages were all high except the 3.3V and it probably had too much HF ripple upsetting the logic board. I was lucky the overal deterioration of the electrolytics caused symptoms I couldn't ignore. There's a couple of small electrolytics on the primary side that can cause gradual regulation failure as the ESR increases - capacitors with high ESR get a degree of self heating from the ripple current, if allowed to cool the ESR increases a lot with the result that the PSU can go bang if the mains goes off for a while and comes back on. One of these critical electrolytics is only 1uF - not hard to find a non-electrolytic replacement small enough to fit. If your's is anywhere near 10 years or more old, I'd reccomend a recap before it does go bang. Use the best high temp - low ESR electrolytics you can get hold of. I got 10uF multilayer ceramic chip capacitors to pad the 6 secondary side smoothers from a scrap LCD TV, but you should be able to order similar from the likes of Farnell. I may have been involved in its manufacture. Does it have an 'N' in the serial number? The PSU was bought in assembled from a reputable manufacturer but we didn't control the AVL for the parts in it. I am very particular about electrolitics. -- Tony |
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#7
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"Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? The PSU was working (sort of) but the voltages were all high except the 3.3V and it probably had too much HF ripple upsetting the logic board. I was lucky the overal deterioration of the electrolytics caused symptoms I couldn't ignore. There's a couple of small electrolytics on the primary side that can cause gradual regulation failure as the ESR increases - capacitors with high ESR get a degree of self heating from the ripple current, if allowed to cool the ESR increases a lot with the result that the PSU can go bang if the mains goes off for a while and comes back on. One of these critical electrolytics is only 1uF - not hard to find a non-electrolytic replacement small enough to fit. If your's is anywhere near 10 years or more old, I'd reccomend a recap before it does go bang. Use the best high temp - low ESR electrolytics you can get hold of. I got 10uF multilayer ceramic chip capacitors to pad the 6 secondary side smoothers from a scrap LCD TV, but you should be able to order similar from the likes of Farnell. I may have been involved in its manufacture. Does it have an 'N' in the serial number? Didn't look and its wedged in the AV stack with me watching TV its decoding. The PSU was bought in assembled from a reputable manufacturer but we didn't control the AVL for the parts in it. I am very particular about electrolitics. Something I should have made a note of is the part number of the TOPswitch chip - if at any time the PSU blows, the chip usually shatters making the number unreadable. Although I did add a ZNR varistor to the mains connector while I had the PSU board out - its a bit OTT really, the PVR is fed by a UPS with built in supression and that is distributed to the AV stack by a socket strip which also has surge supression. You'll need to be quite a bit particular about your electrolytics to find better than the 3x 220uF/35V smoothers directly on the rectifier cathodes - they were pretty good even after 10 years - all the other electrolytics should be replaced with top quality low ESR types. |
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#8
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ian field wrote:
"Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? The PSU was working (sort of) but the voltages were all high except the 3.3V and it probably had too much HF ripple upsetting the logic board. I was lucky the overal deterioration of the electrolytics caused symptoms I couldn't ignore. There's a couple of small electrolytics on the primary side that can cause gradual regulation failure as the ESR increases - capacitors with high ESR get a degree of self heating from the ripple current, if allowed to cool the ESR increases a lot with the result that the PSU can go bang if the mains goes off for a while and comes back on. One of these critical electrolytics is only 1uF - not hard to find a non-electrolytic replacement small enough to fit. If your's is anywhere near 10 years or more old, I'd reccomend a recap before it does go bang. Use the best high temp - low ESR electrolytics you can get hold of. I got 10uF multilayer ceramic chip capacitors to pad the 6 secondary side smoothers from a scrap LCD TV, but you should be able to order similar from the likes of Farnell. I may have been involved in its manufacture. Does it have an 'N' in the serial number? Didn't look and its wedged in the AV stack with me watching TV its decoding. The PSU was bought in assembled from a reputable manufacturer but we didn't control the AVL for the parts in it. I am very particular about electrolitics. Something I should have made a note of is the part number of the TOPswitch chip - if at any time the PSU blows, the chip usually shatters making the number unreadable. In this product or just SMPS in general? The part is a Power Integrations TOP244P according to my schematic. Although I did add a ZNR varistor to the mains connector while I had the PSU board out - its a bit OTT really, the PVR is fed by a UPS with built in supression and that is distributed to the AV stack by a socket strip which also has surge supression. You'll need to be quite a bit particular about your electrolytics to find better than the 3x 220uF/35V smoothers directly on the rectifier cathodes - they were pretty good even after 10 years - all the other electrolytics should be replaced with top quality low ESR types. The 220uF are V low ESR types 56mohm United Chemi Con, C8 33uF is low ESR 240mohm. The rest are Gen purpose 200hr@85C, although I would have gone for 2000@105C preferably if I'd had the AVL control. Everything was designed for low heat production to avoid fans. -- Tony |
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#9
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"Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? The PSU was working (sort of) but the voltages were all high except the 3.3V and it probably had too much HF ripple upsetting the logic board. I was lucky the overal deterioration of the electrolytics caused symptoms I couldn't ignore. There's a couple of small electrolytics on the primary side that can cause gradual regulation failure as the ESR increases - capacitors with high ESR get a degree of self heating from the ripple current, if allowed to cool the ESR increases a lot with the result that the PSU can go bang if the mains goes off for a while and comes back on. One of these critical electrolytics is only 1uF - not hard to find a non-electrolytic replacement small enough to fit. If your's is anywhere near 10 years or more old, I'd reccomend a recap before it does go bang. Use the best high temp - low ESR electrolytics you can get hold of. I got 10uF multilayer ceramic chip capacitors to pad the 6 secondary side smoothers from a scrap LCD TV, but you should be able to order similar from the likes of Farnell. I may have been involved in its manufacture. Does it have an 'N' in the serial number? Didn't look and its wedged in the AV stack with me watching TV its decoding. The PSU was bought in assembled from a reputable manufacturer but we didn't control the AVL for the parts in it. I am very particular about electrolitics. Something I should have made a note of is the part number of the TOPswitch chip - if at any time the PSU blows, the chip usually shatters making the number unreadable. In this product or just SMPS in general? The part is a Power Integrations TOP244P according to my schematic. Would you consider scanning & posting that please??? May I suggest News:alt.binaries.schematics.electronic to upload. The 33uF you mentioned - the only 33uF I remember seeing was the 400V mains rectifier reservoir, this had wire leadouts instead of the riveted tags on high ripple current parts, I found a suitable replacement with proper lugs - requiring new holes to be drilled. |
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#10
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"ian field" wrote in message news:5ZkZn.141157$_F1.130807@hurricane... "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: "Tony" wrote in message ... ian field wrote: Having turned out not to have been affected by the end of InView EPG service - my FVRT90 promptly died. When I went to use it the power LED came on and then it froze, so I unplugged it for 30 seconds and plugged it back in, whereupon the 7 segment display run through the Klingon alphabet and then went blank. Hopefully it only needs a PSU recap or dry joints sorting out - otherwise I'll have to put up with the less than favourite Techwood (Vestel) and the POS Nikkai barebones. Does it do that every time you cold boot it now? Could be the flash is worn out or the drive is knackered. I think the test pattern comes up when there are channels stored but the drive is not formatted (ie it thinks its in the factory). I'm not entirely sure. A full PSU recap fixed it - its my favourite PVR so I beefed up the main smoothing electrolytics with 10uF multilayer ceramic chip capacitors on the print side. There's also a 1uF electrolytic in the regulation circuit on the primary side, if this fails the PSU can go bang - it wasn't hard to find a non-electrolytic 1uF that will never dry out. The mains rectifier reservoir capacitor was a flimsy ordinary type with lead wires instead of riveted tags like this component should have - I drilled new holes and fitted a propper one. All of the electrolytics (except the 3 directly on the cathodes of the 3 rectifiers) looked cheap & nasty - the ESR readings didn't look all that bad, but evidently too high for the PSU to work correctly. Cool, useful to know when mine goes. Perhaps the 12v for the drive went down. Did you find the faulty location(s)? The PSU was working (sort of) but the voltages were all high except the 3.3V and it probably had too much HF ripple upsetting the logic board. I was lucky the overal deterioration of the electrolytics caused symptoms I couldn't ignore. There's a couple of small electrolytics on the primary side that can cause gradual regulation failure as the ESR increases - capacitors with high ESR get a degree of self heating from the ripple current, if allowed to cool the ESR increases a lot with the result that the PSU can go bang if the mains goes off for a while and comes back on. One of these critical electrolytics is only 1uF - not hard to find a non-electrolytic replacement small enough to fit. If your's is anywhere near 10 years or more old, I'd reccomend a recap before it does go bang. Use the best high temp - low ESR electrolytics you can get hold of. I got 10uF multilayer ceramic chip capacitors to pad the 6 secondary side smoothers from a scrap LCD TV, but you should be able to order similar from the likes of Farnell. I may have been involved in its manufacture. Does it have an 'N' in the serial number? Didn't look and its wedged in the AV stack with me watching TV its decoding. The PSU was bought in assembled from a reputable manufacturer but we didn't control the AVL for the parts in it. I am very particular about electrolitics. Something I should have made a note of is the part number of the TOPswitch chip - if at any time the PSU blows, the chip usually shatters making the number unreadable. In this product or just SMPS in general? The part is a Power Integrations TOP244P according to my schematic. Would you consider scanning & posting that please??? May I suggest News:alt.binaries.schematics.electronic to upload. For some reason clicking the link I gave doesn't take me to the group - has anyone spotted what I mucked up? |
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