Touchless: What i would know is if jaycar could be a cheap "playable" begginning instrument or just a toy.
I know what it means learn musical intruments, I study, play and teach for 20years classical guitar, piano, mandolin and sax, unlike some other colleague, I suggest to my beginner students to start with cheap instruments otherways some drawers would be crowded by Ramirez, Selmer, Petrof and other professional instruments
at this link: http://www.element14.com/community/groups/theremin-general-resources?view=documents
there are schematic and photos of Enkelaar Kees, the schematic is very similar to jaycar with some mods that could be done to a standard jaycar.
When i have a bit of time to end the standard jaycar kit, i'll try the mods to make it more like the kees
ok...big problem!
i received the mkII version of the kit that is a bit different from the older one, i soldered all the components, mounted the antennas and placed in the case
I tried to setting it like is written on the instructions but i found that T2 and T3 can be adjusted full clockwise or anticlockwise until stops cause seem to be stripped the same for VR3
no sound exit from internal speaker, just a weak high pitch sound exit from internal speaker when i connect rca out to an amplifier and touch the antennas.
I powered the it with a 12v 7ah sla battery or a 12V dcv stabilized wall power supply
I measured 8,90v DCV between TP GND and TP1 and 0 between TP GND and TP2 or TP3 and there is no way to raise it turning T4 or VR3
What did I do wrong?
thanks thierry...great helps from you
however the i saw that the the small cilinder that you can see from the bottom in the components T3 and T4 seem to be cracked...could be this the problem?
have the vr3 trimmer a limit or it turn clockwise or counterclockwise to infinity?
If something is cracked, this might always be a problem... In ever case, the variable inductors T1, T2, T3 and T4 may never be adjusted with a normal screwdriver since all metal tools do not only falsify the results but they risk also to destroy the ferrite core. You only may use special RF alignment tools which are made of plastic or ceramic for that.
The VR3 trimmer is (depending on what has been in stock at Jaycar's) a one-turn, a 3 turn or a 10 turn version. So it should always have limits after one of the indicated number of turns.
If you already broke the variable inductors, feel free to contact me by email if you want to send me your circuit board in in order to get it fixed and pre-adjusted.
I used a plastic screwdriver but i think that there was very old cause the white paint on the adjustment screw jumped out immediately when i touch it
i wrote to seller to try to have a replacement for the inductors ,i'll wait an answer for my request
ill tell you what they say
If i can send you only the circuit i will be good cause i could save on shipping costs
some news from italy...(excluding Costa Cruisers and siberian winds)
the kit arrived with the coils broken, the internal capacitor was cracked, maybe a construction defect.
I asked to australian ebay seller if he could send me the parts needed and after some several email in which he responded to me with unkind and unprofessional way i decided to ask directly to jaycar and they responded to me very fast and sent me the parts for free.
The parts take a months to arrive in italy with dhl and in this time i tried the circuit mounting the broken coils and putting a 150pf cap in parrallel to pins 1 and 3 of the coils. The theremin now works and i can play it
Thanks to Thierry that are giving to me big helps, i'm bulding ordinary antennas from 2 chromed copper pipes that i bought from a hydraulic shop and i'll do some mods to make this little "toy" more versatile.
New antennas are very easy to bend...some suggestion about make new antenna more solid and preserve the shape?
I thought to fill the volume antenna with a some polimer paste like polyclay
to be continued...
You must be logged in to post a reply. Please log in or register for a new account.
