Search found 747 matches
- Sun Mar 05, 2023 5:48 pm
- Forum: Everyones Projects
- Topic: Ground fault in old CD player?
- Replies: 3
- Views: 4382
Re: Ground fault in old CD player?
Not sure what you mean about meter resistance. 70mv is more than enough to generate the 30ma that will trip the rcb. I would check any live to case caps in the ac input of the teac. Maybe worth looking at the 70mv with a scope to see just what sort of shape the DC is. Ok thanks for input Nick, I've...
- Sun Mar 05, 2023 2:16 pm
- Forum: Everyones Projects
- Topic: Ground fault in old CD player?
- Replies: 3
- Views: 4382
Re: Ground fault in old CD player?
I thought of another explanation, a fault in the Variac earth post connection. Unlikely because the Variac wasn't in circuit when it first tripped.
Eliminated by using a different earth post.
Eliminated by using a different earth post.
- Sun Mar 05, 2023 2:09 pm
- Forum: Everyones Projects
- Topic: Ground fault in old CD player?
- Replies: 3
- Views: 4382
Ground fault in old CD player?
I was testing a passive balanced preamp I've built for a friend, but on playing music through it and attempting to scope the output my RCD trips. I was taking a balanced output from an old TEAC VRDS player and after much elimination I think I've identified there's a ground fault somewhere in the TEA...
- Fri Mar 03, 2023 2:04 pm
- Forum: Computer Audio
- Topic: Streaming DAC/ Pre with Balanced Outputs
- Replies: 7
- Views: 7540
Re: Streaming DAC/ Pre with Balanced Outputs
Me too ref all these ultra neat solid state builds. My projects going forward only in my head of course are: Must build an AD1 amp….. Must build with those idh valves a bit like px4 Must build another 6em7 amp something about it dht’s cant do Must cut the magnet off my ae1’s and bolt on a field coi...
- Fri Mar 03, 2023 7:51 am
- Forum: Computer Audio
- Topic: Streaming DAC/ Pre with Balanced Outputs
- Replies: 7
- Views: 7540
Re: Streaming DAC/ Pre with Balanced Outputs
Check out Tony's 'New Dilemma' thread https://www.audio-talk.co.uk/phpBB3/viewtopic.php?t=8633 I've been watching those DAC build threads, fascinating but it took me years to get my head around valves, I think that fiddly stuff is beyond me. My soldering tool of choice is a D24 Hakko bit. Although ...
- Wed Mar 01, 2023 5:10 pm
- Forum: Computer Audio
- Topic: Streaming DAC/ Pre with Balanced Outputs
- Replies: 7
- Views: 7540
- Wed Mar 01, 2023 8:34 am
- Forum: Computer Audio
- Topic: Streaming DAC/ Pre with Balanced Outputs
- Replies: 7
- Views: 7540
Streaming DAC/ Pre with Balanced Outputs
Hi all. My main system, which uses my DIY power amp with balanced inputs, uses the Cambridge Audio Azur 851N for all digital sources. It's a very convenient device, with multiple digital sources, network streaming and volume attenuation. I very much like the sound, though of course I'm always up for...
- Mon Feb 06, 2023 8:43 pm
- Forum: Valves
- Topic: What are the oldest affordable valves you can still buy?
- Replies: 13
- Views: 8832
Re: What are the oldest affordable valves you can still buy?
I use old globe DHT triodes for my builds and I have quite a boxes of Cunningham, RCA, and many others dating from 1920s, 30s. My opinion they sound great, I like the 26 for input with 71A driver and 45 output. 01A are similar to 26 with half the anode current and there are absolutely tons of them d...
- Wed Jan 18, 2023 8:09 am
- Forum: Everyones Projects
- Topic: Fun with Feedback
- Replies: 239
- Views: 60416
Re: Fun with Feedback
Nice build. Late query. I like the circular grill valve bases, where are they from?Cressy Snr wrote: ↑Fri Jan 06, 2023 10:24 pm Ooh look! Pentodes in the parlour (good name for an arty band) you know, just to see how it sounds with the Mission 773 floor standers like:
73E179F8-08DE-4414-A353-DF10215E41E7.jpeg
- Sun Jan 15, 2023 9:45 pm
- Forum: Everyones Projects
- Topic: Help before I lose my sanity
- Replies: 17
- Views: 8798
Re: Help before I lose my sanity
In this page...http://www.valvewizard.co.uk/heater.html Merlin Blencowe states... Rule number one is that the heater supply must have a DC connection to audio ground. This may be a direct connection or an elevating circuit (see shortly). This is equally true for AC or DC supplies. Leaving the heater...
- Sat Jan 14, 2023 9:37 pm
- Forum: Everyones Projects
- Topic: Help before I lose my sanity
- Replies: 17
- Views: 8798
Re: Help before I lose my sanity
I'm still intrigued by the original fault. The missing earth connection can't have caused that can it?
- Sat Jan 14, 2023 8:50 pm
- Forum: Everyones Projects
- Topic: Help before I lose my sanity
- Replies: 17
- Views: 8798
Re: Help before I lose my sanity
Good to have a variac. One problem might be that getting a Champ right in the first place might be part of the process. Guitar amps are not like hifi amps. If you build something hifi-ish and put a guitar through it, it can sound pleasant. But guitar amps have enormous gain and Champs use one valve...
- Sat Jan 14, 2023 7:58 pm
- Forum: Everyones Projects
- Topic: Help before I lose my sanity
- Replies: 17
- Views: 8798
Re: Help before I lose my sanity
And the final test for tonight, with plate connections restored and secondary fuses in place, DC voltage across the bleed resistor measures 452V with about 160mV ripple.
- Sat Jan 14, 2023 7:51 pm
- Forum: Everyones Projects
- Topic: Help before I lose my sanity
- Replies: 17
- Views: 8798
Re: Help before I lose my sanity
Did the fuse go on the wind up from 0? I'll repeat the test. I may have only done the wind up with heaters only, which was successful. Interesting. Firstly, after a rest I reviewed the physical connections against the circuit I posted. The earth to power ground was missing. I added that (at the far...
- Sat Jan 14, 2023 7:45 pm
- Forum: Everyones Projects
- Topic: Help before I lose my sanity
- Replies: 17
- Views: 8798
Re: Help before I lose my sanity
This may not be helpful but having built several 'fender champs' the 'simple' psu is a feature of its erm, magic. One ecc83 and one el84 ( or 6sl7/ 6v6) really doesn't need much to get rocking but otoh it is only a tiny on/off sort of amp. 8 inch speaker sounds crap too! The fender deluxe is hugely...