how is the board grounded? is there a pin1 header on the board?
OPEN SOURCE DIY Mic Project - ORS 87 - Stripped Down u87
- Thread starter Wordsushi
- Start date
Help Support GroupDIY Audio Forum:
It looks like a ground loop or imperfect connection between the body parts and the PCB GND.
*Is the fan on?
*Is the fan on?
That's what I was thinking
Body parts/head basket/meshes, oxidized, dirty
*Good protection against RF interference is not achieved
In such situations, to find out if the disturbances are electromagnetically induced due to the shielding (Faraday cage) or electrically (for example through the xlr cable/connector), I completely put the microphone in a stainless steel kitchen pan, which I connect to the GND of the cable XLR.
Or in a large empty metal can.
Or in a large empty metal can.
@Wordsushi
Stereo ORS87 looks beastly!
I really like a lot.
Sounds realistic! In some spatial setups in conjunction with other microphones it would do multidimensional wonders!
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Thank you! Taking it out of an 87 style body and putting it into a round headbasket body made a huge difference. I'm very pleased with this one. I'm going to have to make some plans to use it. Maybe I'll have to do some of that stupid ASMR stuff with it.@Wordsushi
Stereo ORS87 looks beastly!
I really like a lot.
Sounds realistic! In some spatial setups in conjunction with other microphones it would do multidimensional wonders!
The Nano however is dead. I had tried a different 103 style body shell and had the same issue.
Arienne gave me some pointers after identifying the noise as 2.4ghz wifi, which makes sense because my booth is not far from the router (which can't be moved).
I had XLR 1 connected to the ground plane on the board instead of just to the body, which she said was causing a loop. So, I altered the PCB and rewired it and I must have borked it somewhere because now I have no signal and 48v reading everywhere. I'm at a loss as to why this one and not the other one or the larger body ORS87s I've built, so I'm just going to chalk this one up as a loss. I've started stripping the board for the parts to rebuild another one the way I did the first one again. Live and learn. At least I know now I like this combination of Bai Fei Li k87 capsule and Ali T-13 transformer on this one.
I hope that in the end you will identify the real cause of the problems related to the interference produced by the wi-fi systems and ways to solve them. It is a broader topic, of general interest, in the future it will be an increasing challenge. I think the topic deserves a separate dedicated thread. We practically live in an ocean of electromagnetic radiation of many kinds, frequencies, intensities, etc.
The capsule from the BeiFeiLi microphone used with good results, could it be one of the ones sold separately on Ali..? You are in the best position to identify it.
Isn't it more advantageous to buy only the capsule and not the whole microphone? We have many good bodies and components waiting to be used.
Looking for a step by step, or video of assembly of ORS board? So far I've been able to put circuits and capsules into a microphone, but full on assembly I need some help. The breadboard pic with blue and red wiring looks super helpful, but I feel I could use a tutorial.
Welcome to the group!
Have you considered buying a PCB to populate with components(it would be easier to do) or have you not yet decided which way to go?
Perfboard, breadboard,point-to-point:
very cheap but more complicated.Unfortunately there is no video tutorial for building ORS87, whichever version you choose.
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I have the ORS 87 v1.1 PCBWelcome to the group!
Have you considered buying a PCB to populate with components(it would be easier to do) or have you not yet decided which way to go?
Perfboard, breadboard,point-to-point:
https://groupdiy.com/threads/open-source-diy-mic-project-ors-87-stripped-down-u87.86814/post-1144040
That should be a pretty comprehensive bill-of-materials. Maybe attach a photo of the board so we can verify the component designators vs the values? I'm not gonna spend even more time digging through the rest of this thread for that
Excellent. I assume that you have already purchased all the electronic components, the capsule and its support, transformer, microphone body, other parts, etc.
Already some members who have used this PCB have posted pictures, or will surely be kind enough to post more, detailed, relevant, with information, directions. Including jFET BIAS tuning methods.
Be sure to read the entire thread from the beginning and other threads about the U87.
Arm yourself with patience and perseverance. Good luck!
I have a puzzle: why do you mind the drawing of PCB v1.1, red and blue paths/traces? Ignore them, they are on the PCB , just focus on the correct positioning of the components. Have the circuit diagram for help.
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This is the only pic I have of a populated Homero V1.0 board. Hope this helps.
Also, just in case you need it, the tranformer pads connect like this.
P- = tx2
P+. = tx1
S- = tx4
S+. =tx3
Yes, the Bai Fei Li capsule with the black ring is available on Aliexpress for about $38.
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Found another one build by @Wordsushi
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untamedfrontier
Member
While I'm still waiting for my boards to arrive; I've also ordered the baifeili 87 capsule, HL-95 body, and a shockmount from aliexpress, but I assume the HL-95 body is not going to arrive with any sort of XLR connector.
I'm assuming this one will be the best XLR connector for our purposes: Amphenol Audio AC4-MIC
Any other suggestions or recommendations? I saw a switchcraft QG5M as a similar option but $15 for an XLR connector seems silly
EDIT: strikethrough of shared part as it's a 4 pin XLR and not the right choice for a standard build. AC3-MIC is the 3 pin XLR connector in the same series
I'm assuming this one will be the best XLR connector for our purposes:
Any other suggestions or recommendations? I saw a switchcraft QG5M as a similar option but $15 for an XLR connector seems silly
EDIT: strikethrough of shared part as it's a 4 pin XLR and not the right choice for a standard build. AC3-MIC is the 3 pin XLR connector in the same series
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Built by @Highlander
