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<blockquote data-quote="vlammie" data-source="post: 480428" data-attributes="member: 270173">Hi LlewThanks for your tips for measuring elco's. ESR meters do not seem to be very common. I see a lot of home made devices in the internet. The values you get seem to be a little bit arbitrary. In fact you should now the manufacturers specification to be able to judge wetter or not a reading is acceptable.Talking about R3.&nbsp; I have used 3W devices, which are a little bit larger as the original 2W types, but mounted them in a different way. I have stuck the body of the resistor in the opposite hole and have the bended lead in the hole were the body normally is. In this way it is much further away from C3 and C12 and has more room to &quot;breath&quot;.I also discovered that my back up SMPS was actually not switching off the switchable voltages (21, 30, 8 and 5 V) due to a defect transistor Q5 . This device had a shorted CE. The receiver however worked okay and looked swiched OFF were actually the voltages were still ON. (clock in display). I did not measure the power consumption but this might be much higher then when the switchable voltages are really OFF. Transistor Q5 (2SA1273/2SA928A in my devices) seem to be dimensioned to narrow. Vce max. for these devices is 30 V. In the OFF stage however the voltage accross collector-emitter is continously more then 30 V. The SMPS is still switching to keep the 12 V and 5VS line &quot;live&quot;. So Q5 will continuously see more then 30V across CE. I have replaced this transistor for a BD229 which i had laying around here. This device can withstand higher CE voltages, although Ic max is a little bit lower (1.5A&nbsp; versus 2A) But I don't expect currents that high in the 30V line. Hopefully I don't need my spare soon, but you never know. The devices get pretty hot and this is indead not very good for the lifetime of the elco's. I might have to replace some more soon. But for now I am a happy AD-3000 viewer again.<img src="https://www.satellites.co.uk/styles/default/xenforo/smilies/smile.png"&nbsp; class="smilie" loading="lazy" alt=":)" title="Smile&nbsp; &nbsp; :)" data-shortname=":)" /></blockquote>

[QUOTE="vlammie, post: 480428, member: 270173"] Hi Llew Thanks for your tips for measuring elco's. ESR meters do not seem to be very common. I see a lot of home made devices in the internet. The values you get seem to be a little bit arbitrary. In fact you should now the manufacturers specification to be able to judge wetter or not a reading is acceptable. Talking about R3. I have used 3W devices, which are a little bit larger as the original 2W types, but mounted them in a different way. I have stuck the body of the resistor in the opposite hole and have the bended lead in the hole were the body normally is. In this way it is much further away from C3 and C12 and has more room to "breath". I also discovered that my back up SMPS was actually not switching off the switchable voltages (21, 30, 8 and 5 V) due to a defect transistor Q5 . This device had a shorted CE. The receiver however worked okay and looked swiched OFF were actually the voltages were still ON. (clock in display). I did not measure the power consumption but this might be much higher then when the switchable voltages are really OFF. Transistor Q5 (2SA1273/2SA928A in my devices) seem to be dimensioned to narrow. Vce max. for these devices is 30 V. In the OFF stage however the voltage accross collector-emitter is continously more then 30 V. The SMPS is still switching to keep the 12 V and 5VS line "live". So Q5 will continuously see more then 30V across CE. I have replaced this transistor for a BD229 which i had laying around here. This device can withstand higher CE voltages, although Ic max is a little bit lower (1.5A versus 2A) But I don't expect currents that high in the 30V line. Hopefully I don't need my spare soon, but you never know. The devices get pretty hot and this is indead not very good for the lifetime of the elco's. I might have to replace some more soon. But for now I am a happy AD-3000 viewer again. :) [/QUOTE]

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