Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - flester

Pages: 1 ... 3 4 [5] 6 7 ... 9
61
Amplifier Discussion / Hotone Nano Amp Heads
« on: August 10, 2018, 05:46:15 PM »
Have been looking at small SS amp heads with a view to building 10" cab. The Hotone ones for example.  http://www.hotoneaudio.com/products/nanolegacy/Amplifier1/2016/1114/184.html
Are these any different to a small practice amp without a speaker? Any idea of what electronics they use?

Sent from my SM-G935F using Tapatalk


62
The Newcomer's Forum / Re: Orange Crush 12 repair
« on: August 03, 2018, 12:05:01 PM »
Picture now attached

Sent from my SM-G935F using Tapatalk


63
The Newcomer's Forum / Re: Orange Crush 12 repair
« on: August 03, 2018, 12:04:15 PM »
I did break the earth connection to chassis as shown in this photo but am fairly sure the issue was there before that

Sent from my SM-G935F using Tapatalk


64
The Newcomer's Forum / Re: Orange Crush 12 repair
« on: August 03, 2018, 12:00:53 PM »
If it failed once and it fails again following the same scheme:
A lot of ancient/recent FX/boutique amp designs use an unprotected TL072 or similar as input stage.
Often the poor input transistor gate is hard-tied to the phone tip without any protection. Suggestion: Insert a series resistor of 4k7 or 10k between Tip and OpAmp, connect two antiserial Zener diodes 2,7V from OpAmp input to GND.
From now on spikes or DC thumps from connecting DC ring-switched active basses/guitars are swallowed by resistor and zener. The gate junction stays alive a bit longer. And once somebody starts to unsolder an OpAmp: A socket is always handy.
One fine day you may want to swap a TL052 in. Or what ever crosses your mind...
I replaced the Overdrive plot and broke the pcb traces in the process. I then replaced the broken trace with a wire link (connected to R7 as  shown). When I ove the pot slightly I get either a weak output with a missing sound, or a loud bassy buzz, or a proper overdrive sound. All connections to the pot seem sound. Could there be an issue somewhere other than the pot?

Sent from my SM-G935F using Tapatalk


65
Tubes and Hybrids / Re: What to do with this old Pye radio?
« on: August 02, 2018, 05:23:47 AM »
If the capacitors have paper sleeves, a good trick to upgrading but keeping the "vintage" look is to put new caps in the old paper sleeves.  Done correctly, nobody will tell the difference.
Thanks. I think the full rebuild is beyond me at present so its on a shelf now with an fm radio wired to the speaker. To the casual observer I have a working vintage radio and the original unit is safe inside where it's been for 50 years.

Sent from my SM-G935F using Tapatalk


66
The Newcomer's Forum / Re: Centre Negative DC Jack
« on: July 12, 2018, 05:30:17 AM »
This one draws 0.5A https://www.velleman.eu/products/view/?id=9181

And this one 0.8A
https://www.kemo-electronic.de/en/Light-Sound/Amplifier-Splitter/Modules/M032N-Amplifier-12-W-universal.php

I thought maybe the LM386 could go in my pedal board/box as it is pedal sized and plugs into an external speaker

Sent from my SM-G935F using Tapatalk


67
The Newcomer's Forum / Re: Centre Negative DC Jack
« on: July 12, 2018, 04:02:34 AM »
They are amps I built myself with 9v battery or wall wart options. I believe I just need to change the wiring from centre pos to centre neg as shown in picture. I take the point about current requirements though. One of the amps uses an lm386 which which may not need much but another uses a Kemo 12w module so it may not work for that one.

Sent from my SM-G935F using Tapatalk


68
The Newcomer's Forum / Re: Centre Negative DC Jack
« on: July 10, 2018, 11:32:07 AM »
OK I think I've got it. Basically I need to reverse the polarity of all the leads connected to the DC jack.
https://goo.gl/images/awuayZ

Just to clarify, I will keep the pedals centre negative and convert my amps to be the same. That way all my pedals and battery amps can be powered by an effects power supply. Might also add diodes to the amps for reverse protection.

69
The Newcomer's Forum / Re: Centre Negative DC Jack
« on: July 03, 2018, 07:49:34 AM »
Pedals are Behringer delay, Behringer tremolo pan,  Danelectro Fab Overdrive, Mooer Shimverb.  Pedals all have centre negative jacks and use 9v. I know I need to reverse the leads from jack to board to use the external ps but not sure how to connect the internal battery.

Sent from my SM-G935F using Tapatalk


70
The Newcomer's Forum / Centre Negative DC Jack
« on: July 02, 2018, 09:20:23 AM »
I've been trying to work this out for myself but it's beaten me.

I have a few small amps which can run off a 9v battery, or a wall wart via a DC jack (which disconnects the battery). I want to change the DC jacks to be 'negative centre' so match my pedals so I can run the amp and pedals from the same supply. Any suggestions for wiring this?

71
Amplifier Discussion / Re: Thinking about building a SS amp
« on: June 16, 2018, 06:03:28 AM »
I like the guitar project. I also took inspiration from Ovation electrics using the Viper body shape.

Sent from my SM-G935F using Tapatalk


72
The Newcomer's Forum / Re: Using 2 Velleman TDA2003 modules
« on: May 08, 2018, 12:03:54 PM »
Will it sound any different if I connect each output to its own speaker? This would be easier as both are already built into complete modules. I could then have mono  or stereo input options. Heres the enclosure with 4ohm car speakers currently fed with an LM386 amp

Sent from my SM-G935F using Tapatalk


73
The Newcomer's Forum / Using 2 Velleman TDA2003 modules
« on: May 04, 2018, 02:47:38 AM »
As mentioned in other posts I have 2 of these. How would I wire both to drive  single speaker? Or 2 speakers maybe?
 http://Https://www.velleman.eu/products/view/?id=9181

Sent from my SM-G935F using Tapatalk


74
The Newcomer's Forum / Re: Orange Crush 12 repair
« on: April 18, 2018, 07:22:12 AM »
You dont need to worry about discharging caps as voltage across them not large enough to be a hazard in small SS amps. Just make sure amp is unplugged when you delve inside. To clean pots, get hold of some contact cleaner spray (Servisol or similar - not WD-40!) Fit the small tube (looks like a straw) into the nozzle and spray for a second or two inside the pots. There should be a small vent hole in the body of the pots into which you poke the tube and spray. Give the jack sockets a blast while you are at it. This is best done by inserting a jack plug to open the spring contacts before spraying. Good luck.
Overdrive pot needs replacement for sure. It is marked B250k but I believe B can be linear or log depending on market? All the pots (gain, overdrive, volume, low, mid, high) are B which guess means probably log?

Sent from my SM-G935F using Tapatalk


75
The Newcomer's Forum / Re: Orange Crush 12 repair
« on: April 14, 2018, 06:50:39 AM »
I didn't have any luck with the video, but from the sound of your description, those pots might just need to be cleaned.
Yes hopefully that might be all it needs. Surprising how simple the circuit seems by the way.  TDA2030 at the heart of ir. Should I be discharching caps before working on it or is that just for tube amps?

Sent from my SM-G935F using Tapatalk


Pages: 1 ... 3 4 [5] 6 7 ... 9