Definitely! Also need to be connected to a non-anodised part.
The DIYA attachment system is not great. Just click the links, the images a huge.
To what? The chassis?
Kit was delivered like this, without any connection. Is it too bad?
Could you explain to me exactly what I have to connect to what?
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Yes, to the chassis, to a non-anodised part. You might need to sand the anodising off. It's safety earth connection and dangerous if you don't have it connected (unless you follow strict double insulation standards, which you are clearly not). Research it
WOW, this is the very kind of project that im looking at doing!
Ive been wanting to build a preamp of my choice, but I thought I wouldnt mind integrating an FM tuner into it also.
I was thinking of using a TEA 5767 FM tuner module and then use the arduino to control the radio, as well as handle an IR remote control to control a stepper motor operated potentiometer to adjust the volume of the internal valve preamp of my choice, by means of an electronic tube volume control, and also control the input selector to either one of the AUX inputs, phono, FM tuner and Bluetooth etc.
Obviously the preamp would only be needed for the FM tuner and phono, so i could have the arduino switch the preamp off to save the life of the tubes by means of a relay, but im not sure how i could remotely control the input selector, unless there are stepper motor controlled switches available?
Either way im keen to work with anyone wanting to build a similar project, im just really suck at coding, so would need help with this.
I would also need to use an LCD or VFD display to display the input selected and radio etc.
Ive been wanting to build a preamp of my choice, but I thought I wouldnt mind integrating an FM tuner into it also.
I was thinking of using a TEA 5767 FM tuner module and then use the arduino to control the radio, as well as handle an IR remote control to control a stepper motor operated potentiometer to adjust the volume of the internal valve preamp of my choice, by means of an electronic tube volume control, and also control the input selector to either one of the AUX inputs, phono, FM tuner and Bluetooth etc.
Obviously the preamp would only be needed for the FM tuner and phono, so i could have the arduino switch the preamp off to save the life of the tubes by means of a relay, but im not sure how i could remotely control the input selector, unless there are stepper motor controlled switches available?
Either way im keen to work with anyone wanting to build a similar project, im just really suck at coding, so would need help with this.
I would also need to use an LCD or VFD display to display the input selected and radio etc.
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Hi Max,
I think I will hijack this thread, pardon me for that. I am interested in just building the attenuator project and as I see on your relay selector board you've attached here, you send the signal from the input relays through the sel_out pins and also have the mute in pins that send the signal to the muting relay. Since I am interested in the muting relay feature, could I just avoid to put the sel out pins and simply send the signal to the muting relay in order to avoid jumpers? By the way, could you help me on the arduino code so I could manually engage the muting relay to mute the preamp ( by long pressing the selector button ) and to have it engaged for a few seconds each time the preamplifier is turned on?
Thanks in advance!
P.S. I understand that many years have passed since your last post, but are there any boards available to send?
I think I will hijack this thread, pardon me for that. I am interested in just building the attenuator project and as I see on your relay selector board you've attached here, you send the signal from the input relays through the sel_out pins and also have the mute in pins that send the signal to the muting relay. Since I am interested in the muting relay feature, could I just avoid to put the sel out pins and simply send the signal to the muting relay in order to avoid jumpers? By the way, could you help me on the arduino code so I could manually engage the muting relay to mute the preamp ( by long pressing the selector button ) and to have it engaged for a few seconds each time the preamplifier is turned on?
Thanks in advance!
P.S. I understand that many years have passed since your last post, but are there any boards available to send?
I am coming back to correct my previous post since I've studied a bit more of the schematic and I understood what you've mentioned about an extra output that might be useful in the future. One critical question though is the power output that leads from the input selector to the mdac. Since I am interested only in the input selector, is that output needed for another purpose or could it be removed from the pcb?
Hey Exelixis,
Sorry for the late reply. I don't know why the thread subscription notification system is so flakey on these forums...
Sure but you will need to power both both boards and have arduino code controlling the mute relay. TBH if you only want relay mute then maybe just implement that yourself separate from the attenuator. It would be a pain to use the input selector just for the mute feature.
Sure, post your code with a specific question.
I can check. I am actually still working on this preamp
Both PCBs need power to run the relays etc. If you are just interested in the attenuator then just don't use or attach the input selector PCB. They can both be run separately easily.
Sorry for the late reply. I don't know why the thread subscription notification system is so flakey on these forums...
Sure but you will need to power both both boards and have arduino code controlling the mute relay. TBH if you only want relay mute then maybe just implement that yourself separate from the attenuator. It would be a pain to use the input selector just for the mute feature.
Sure, post your code with a specific question.
I can check. I am actually still working on this preamp
Both PCBs need power to run the relays etc. If you are just interested in the attenuator then just don't use or attach the input selector PCB. They can both be run separately easily.
I would like to build your 5 Volt and +/- Power Supplies. Do you sell the PCB's for these power supplies? Will the transformers work with 115/120 Volt mains? I love your Arduino Preamp Design.
Hey mrsavage, I checked I have no PCBs left. But I have uploaded all the PCB files here many times, all you need to do is download the files and then upload the eagle brd file to either PCBs.io - Custom PCB Service or OSH Park ~ and you can order your own for pretty cheap
How much current does the +/- Supply Need?
Since I live in the United States of America, I need a split primary on the
input of the power transformer. How many milliamps output does this supply
need? I found several split primary transformers, but which one is best?
Let me know if you have any advice on this subject. Great project.
Since I live in the United States of America, I need a split primary on the
input of the power transformer. How many milliamps output does this supply
need? I found several split primary transformers, but which one is best?
Let me know if you have any advice on this subject. Great project.
At this point you are really only using the input selector, right? Not hard as long as you can change the arduino code and design your own arduino controlled FM and motor pot modules.
Since I live in the United States of America, I need a split primary on the
input of the power transformer. How many milliamps output does this supply
need? I found several split primary transformers, but which one is best?
Let me know if you have any advice on this subject. Great project.
Exactly which power supply do you mean? I made 2:
A simple but low noise LT1761/LT1964 PSU design
Compact DIY friendly dual TPS7A3301 power supply
Maybe post in either of those threads to keep the topic clean
Please look over my Eagle Conversion to 120Volts
Attached is my first trail to convert your 240-Volt 5-Volt Power Supply Eagle files to 120-Volt 5-Volt Power Supply Eagle files. I know NOTHING about Eagle. This is the first time I have try using Eagle, so please forgive me for ant mistakes. Let me know what you think of my attempt to make the necessary changes.
Attached is my first trail to convert your 240-Volt 5-Volt Power Supply Eagle files to 120-Volt 5-Volt Power Supply Eagle files. I know NOTHING about Eagle.
This is the first time I have try using Eagle, so please forgive me for ant mistakes. Let me know what you think of my attempt to make the necessary changes.