Thank you for your time Trevor, it's always nice to see these big Rotel receivers get the love they deserve. They were built to a price point way back when, but they could really hold their own...they do need some serious love after all these years though.
Glad to see a new video out although I’m still going through all your older ones and I like all the detail you sometimes take to show the steps. I’m still learning all this stuff and the more detail the better.
It's always a treat to be able to look over your shoulder and I do really enjoy watching but it's your channel and you make the rules, don't feel obliged to over produce content.
It is Saturday night and I didn't plan on watching this whole video, but I couldn't stop. it is like a mystery movie, waiting to see what happens next! I appreciate your work and honesty and the deoxit crowd may not like your comments. My only comment is I think you should bump up that signal meter a little, as vintage audio guys love their deflection.
timestamp 27:41 if they do not like it they can skip it.. I love it when the vedeo is so detailed.. so I can learn from it... that is the reason most of us watch these video's.. the oned that like the 12 minutes video's there are enough other channels that show noting and is like this is wrong I did this it is fixed the end.. and they can skip over the detailed parts in your video's.... thank you for making these awesome repair video's
They are by design stable so the value/ESR shouldn't change unless they are damaged by reverse voltage or over voltage, temperature. I'm going to do some research deeper into tantalums and their failures
Thankyou for a great video. 👍 I am wondering why the use of deoxidising spray on the switch contacts would cause them to arc more than they otherwise would?
I am always impressed by the solution-finding approach. Question: have you replaced all the tantalum capacitors with electrolytic capacitors? I often do esp. like to use tantalum for small values
The usual failure roadmap of shorted tantalum caps is climbing ESR, followed by thermally induced breakdown and failure to a short. However, this is usually in the presence of AC ripple or transient spikes. Those back to back caps have age related ESR climb possibly accelerated due to reverse bias. I don't trust old tantalums one bit. Even when employed for low voltage bypass they can test good for value, but be virtually useless due to age related ESR climb.
If you can't get OEM parts anymore, then you are guessing to what replacement should be based on your opinion not what was originally intended by the guys that designed the circuitry /layout I see this based on the idiots that fix old CRT Televison's and it's the same mantra "change ll the capacitor" People are not going to get into this when they realize you can't parts anymore, and you are pretty much wasting your time Now that NTE has closed down, you can't get every part from DIGI-Key and Mouser Not the semiconductors you're not , so how far can you real go with fixing this stuff ?
Nice to see you back Trevor, unfortunately ROTEL is on the bottom of my list with quality control manufacturing + these like to Rust. 125 WPC and No Film Cap for soft start on Power switch, explains the burnt contacts. This thing was built in 1977, why are there carbon comp resistors. Strong Stereo light.
Yet another change all the capacitor video People don't have time to watch 2 hours of highly boring stuff. Just get to the point , get out of your basement a little bit more
@@TrevorsBench Changing capacitors is not end all be all of fixing things , it's just a quick fixing solution to a bigger problem usually semiconductors
@@johnsenchak Why not just skip the video then? I know I waste my time. But for any reasonable viewer: no, routinely changing caps after about 50 years has nothing to do with failing semiconductors, but with caps that might already have failed or degraded, or in the case that the caps are in fact still good: just as a preventive maintenance. If semiconductors (or passive components to a certain degree) are failing more dramatically, then one would hope to catch that in the measurements (frequency response, balance between the channels, distortion to name a few important ones), hence why those are done here.
Not in the 50mm size needed for replacement. I found the Cornell Dubilier caps for less. Typically, the price of caps has doubled in the last 2-3 years due to inflation and the difference in currency exchange rates
Thank you for your time Trevor, it's always nice to see these big Rotel receivers get the love they deserve. They were built to a price point way back when, but they could really hold their own...they do need some serious love after all these years though.
Glad to see a new video out although I’m still going through all your older ones and I like all the detail you sometimes take to show the steps. I’m still learning all this stuff and the more detail the better.
I hope it keeps you entertained!
It's always a treat to be able to look over your shoulder and I do really enjoy watching but it's your channel and you make the rules, don't feel obliged to over produce content.
Thanks
It is Saturday night and I didn't plan on watching this whole video, but I couldn't stop. it is like a mystery movie, waiting to see what happens next! I appreciate your work and honesty and the deoxit crowd may not like your comments. My only comment is I think you should bump up that signal meter a little, as vintage audio guys love their deflection.
I highly applaud the concept of taking a break now and then!
Really good content Trevor, thanks for posting. Huge thanks for showing (with all the details) your method for repairing the power switch.
Another nice job. I'm glad you're back.
timestamp 27:41 if they do not like it they can skip it.. I love it when the vedeo is so detailed.. so I can learn from it... that is the reason most of us watch these video's.. the oned that like the 12 minutes video's there are enough other channels that show noting and is like this is wrong I did this it is fixed the end.. and they can skip over the detailed parts in your video's.... thank you for making these awesome repair video's
What a job! I thought my Sony V6 was silly big. Fabulous job man
I never found a one week schedule in your work, just watch when you post. Take care.
More often than not, old tantalums have really high ESR... according to my experience.
They are by design stable so the value/ESR shouldn't change unless they are damaged by reverse voltage or over voltage, temperature. I'm going to do some research deeper into tantalums and their failures
Thankyou for a great video. 👍 I am wondering why the use of deoxidising spray on the switch contacts would cause them to arc more than they otherwise would?
I replace tantalum automatically they are usually on their way anyways
I am always impressed by the solution-finding approach. Question: have you replaced all the tantalum capacitors with electrolytic capacitors? I often do esp. like to use tantalum for small values
Huge PS caps, and no soft start. That poor switch! Would adding a triac help take the load off the switch?
It really irks me as a plain and simple hobbiest that deoxit was propped up on forums as the miracle switch and pot cure all.
It's a short term fix
Wow!... 85$ each for those capacitors?! That's crazy!
Heavy markups for profit
The usual failure roadmap of shorted tantalum caps is climbing ESR, followed by thermally induced breakdown and failure to a short. However, this is usually in the presence of AC ripple or transient spikes. Those back to back caps have age related ESR climb possibly accelerated due to reverse bias. I don't trust old tantalums one bit. Even when employed for low voltage bypass they can test good for value, but be virtually useless due to age related ESR climb.
How cold is it up there in Caada eh!
-5C right now
If you can't get OEM parts anymore, then you are guessing to what replacement should be based on your opinion not what was originally intended by the guys that designed the circuitry /layout I see this based on the idiots that fix old CRT Televison's and it's the same mantra "change ll the capacitor" People are not going to get into this when they realize you can't parts anymore, and you are pretty much wasting your time Now that NTE has closed down, you can't get every part from DIGI-Key and Mouser Not the semiconductors you're not , so how far can you real go with fixing this stuff ?
It's ok about Canadian prices. Soon Canada will be the 51st state according to the Orange god.
Prob be better off than the current man-child that's abandoned his job back in October
Nice to see you back Trevor, unfortunately ROTEL is on the bottom of my list with quality control manufacturing + these like to Rust. 125 WPC and No Film Cap for soft start on Power switch, explains the burnt contacts. This thing was built in 1977, why are there carbon comp resistors. Strong Stereo light.
Yet another change all the capacitor video People don't have time to watch 2 hours of highly boring stuff. Just get to the point , get out of your basement a little bit more
Hi John, Seems you haven't yet grasped the concept of capacitor changes and the purpose they serve, keep watching
@@TrevorsBench Changing capacitors is not end all be all of fixing things , it's just a quick fixing solution to a bigger problem usually semiconductors
@@johnsenchak Why not just skip the video then? I know I waste my time. But for any reasonable viewer: no, routinely changing caps after about 50 years has nothing to do with failing semiconductors, but with caps that might already have failed or degraded, or in the case that the caps are in fact still good: just as a preventive maintenance.
If semiconductors (or passive components to a certain degree) are failing more dramatically, then one would hope to catch that in the measurements (frequency response, balance between the channels, distortion to name a few important ones), hence why those are done here.
Mouser and Digikey have K E M E T caps for about $30 each
Not in the 50mm size needed for replacement. I found the Cornell Dubilier caps for less.
Typically, the price of caps has doubled in the last 2-3 years due to inflation and the difference in currency exchange rates