Argg, sorry! I'm very bad writing in english
Sapphire it's sapphire here and everywhere. "Zafiro" would be in spanish but "Sapphire" looks more cool ;-)
Then, there's no bias tune up? Reading older posts and your manual y thought it was.
Zobel filter have no adjustement too? (I was solder everything opcional, zobel filter and all capacitators).
Here it some photos; many thanks and greetings!!
I like the female RCA jacks pictured above. Can you tell me where they came from?
Thanks...
Ok, I will rotate the heatsinks; thanks for the advice 
Rca's where from Audiophonics (Audiophonics - Câbles, Amplificateurs et Accessoires DIY), a French shop. They have a lot of hifi items but the shipping costs are expensive, so the idea is to join some hobby friends and make one order.
Embases RCA - ELECAUDIO ER-105 Embase RCA isolée PTFE (la paire)
Last thing: Does the Zobel filter have necessity to adjust?
Thanks again an greetings!
Rca's where from Audiophonics (Audiophonics - Câbles, Amplificateurs et Accessoires DIY), a French shop. They have a lot of hifi items but the shipping costs are expensive, so the idea is to join some hobby friends and make one order.
Embases RCA - ELECAUDIO ER-105 Embase RCA isolée PTFE (la paire)
Last thing
: Does the Zobel filter have necessity to adjust?Thanks again an greetings!
From the color of your NOS capacitors, I m getting that they are paper in oil or something like that. Most likely of the K75 variety. This is a VERY nice capacitor with dreamy mids, but it tends to roll off highs and lows a bit.
When you start to get an itch to upgrade, check ebay for FT-3 capacitors. These are the best of the russian NOS and they are available in 0.47uF.
Bypassing is putting another capacitor in parallel with the main, to alter its behavior. But since there are already 0.47 FT-3s you can just replace them and not worry about bypassing and stuff.
Here is a link for you
Russian Teflon Capacitor FT-3 0.47uF 470nF 200V 1pc. or more | eBay
Nice build
When you start to get an itch to upgrade, check ebay for FT-3 capacitors. These are the best of the russian NOS and they are available in 0.47uF.
Bypassing is putting another capacitor in parallel with the main, to alter its behavior. But since there are already 0.47 FT-3s you can just replace them and not worry about bypassing and stuff.
Here is a link for you
Russian Teflon Capacitor FT-3 0.47uF 470nF 200V 1pc. or more | eBay
Nice build
Ni-ce. I'm also digging that braided headphone cable.
I noticed you reversed the board that connects to the power switch, and didn't put the little plastic ring around the power push button.
The idea is the LED fits on the board just under the push button, and the plastic bit serves as a light guide to bring the light to the front panel. (I didn't bother on mine either, I just thought I'd mention it.)
I noticed you reversed the board that connects to the power switch, and didn't put the little plastic ring around the power push button.
The idea is the LED fits on the board just under the push button, and the plastic bit serves as a light guide to bring the light to the front panel. (I didn't bother on mine either, I just thought I'd mention it.)
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Damm! You're right! I had inverted the pcb
Anyway, I will change for someone like this
Ah! I have found the noise in the left channel.
It's the 220v blue wires. The electromagnetism generated it's caught by the big condensator.
I will isolate the wires with teflon or with a braided metal connected to earth ¿What do you think?
Greetings!
Anyway, I will change for someone like this
Ah! I have found the noise in the left channel.
It's the 220v blue wires. The electromagnetism generated it's caught by the big condensator.
I will isolate the wires with teflon or with a braided metal connected to earth ¿What do you think?
Greetings!
If you twist the pair of blue wires together you can reduce the electromagnetic flux spilling out. That should probably be enough to get rid of the noise (worked for me). If you need need to use a shielded conduit - metal tube or sleeve, connected to the chassis.
/R
PS Certainly you can replace the power button, just as long as it can be retrofitted on the faceplate without too much trouble.
/R
PS Certainly you can replace the power button, just as long as it can be retrofitted on the faceplate without too much trouble.
The difference is in the hFE grade. -nothing is the mixed bag rank, -10 has lower hFE (100 typ) and -16 higher hFE (160 typ). Manufacturers selling those variations wqill also have that info in the datasheet.
You can also use BD137s or BD139s (higher voltage grades) if they have -16 ranks of those.
BD135-16s were routinely used for bias setting transistors in the late '70s, but I guess the difference in pricing between the 135s and 139s eventually disappeared, so no one is using 135s any more.
Be wary if someone is trying to sell you Philips / NXP parts - these haven't been made in a decade or so. Bit of a shame since those had much higher fT compared to whatever you can get from On Semi, Fairchild or STMicro (50 MHz typ, On Semi part seems a little better).
You can also use BD137s or BD139s (higher voltage grades) if they have -16 ranks of those.
BD135-16s were routinely used for bias setting transistors in the late '70s, but I guess the difference in pricing between the 135s and 139s eventually disappeared, so no one is using 135s any more.
Be wary if someone is trying to sell you Philips / NXP parts - these haven't been made in a decade or so. Bit of a shame since those had much higher fT compared to whatever you can get from On Semi, Fairchild or STMicro (50 MHz typ, On Semi part seems a little better).
As the transistors are only being used as followers, both in the regulation circuits (X-reg, Z-reg) and the diamond buffer (sapphire, bboard), the hFE value isn't critical. I chose the -16 parts as having the highest hFE since in principle this gives the highest input impedance for a given load... they are the easiest to drive, in other words.
You can substitute any voltage class and any hFE bin: 135,137,139 both -10 and -16 types. Personally I wouldn't mix and match but I doubt it makes much difference.
You can substitute any voltage class and any hFE bin: 135,137,139 both -10 and -16 types. Personally I wouldn't mix and match but I doubt it makes much difference.
Thank you Richard, it a relief to here that from you. Actually element14 carry varieties of BD135, but it takes gew day for delivery and I cannot wait, they also now imposed a minimum order of $70 for free delivery or pay $10 for postage. Its ridiculous to pay $10 postage for $0.50 items.
Btw Richard, I did a few mods to my Sapphire Amp. I put some 1000uF caps immediately after the rectifier, bypass the caps and opamp as recommended and now the hums are all gone. Its dead quiet even at full volume. "Love when all the plans comes true".
Btw Richard, I did a few mods to my Sapphire Amp. I put some 1000uF caps immediately after the rectifier, bypass the caps and opamp as recommended and now the hums are all gone. Its dead quiet even at full volume. "Love when all the plans comes true".
When I built the most recent one for myself I changed C1 to Multicap PPFXS and all the metal film resistors to Welwyn/PRP. Call it an insurance policy. The kit Vishays are perfectly good resistors though. The included cap C1 is also more than reasonable, but of course if you are willing to invest $30 or more in a substitute pair I think you can do better.
Perhaps fortunately, no one has come along to offer an "audiophile" version of the BD135!
Perhaps fortunately, no one has come along to offer an "audiophile" version of the BD135!