I had bought one of these Anomoly Phone-Jams (www.phone-jam.com) on ebay for use as phone patch. It calls for a 3-Pin mini DIN power supply, and is clearly marked 12 v input on the unit, but have come to realize the power supply they sent me with it is a 3-pin 28 vct Condor desk top Power supply..
I rummaged through my power supplies and have a 12v 4 pin that used to go to a tv, and tried to find an 4pin to 3pin adapter online with no luck, and what few 3pin din 12v power supplies I can find are in the $50-$60 price range.
Assuming this unit hasn't been damaged, what's my best option to apply power to this thing at a minimum cost?
If your having trouble finding the proper power unit for that, you may have to crack it open and have a look at that plug's situation on the inside. Since that thing takes 12vac, looks to me like all you need is a 12vac transformer with a center tap. Should not be that big a problem getting it going.
RFB
I assume you mean just cutting a plug off a 12v supply and wiring straight. That was my initial thought, but what worried me was the 3 pins, -I don't know why some dins have 3, others 4, 5, 6.. etc. I'm unfamiliar with the concept of all these pins for a 12v connection..
And that's what throws me off in just splicing it in.
I've got some 12v adapters with two contact connectors
(I guess the "center tap" you mention with the hole with the outer sleeve type).
.
.. By the way, I thought your name really was RF Burns until I listened to the last Low Power Hour!
Well my guess at looking at the item off the main page at the power connector on the back is one of two ways this thing gets power:
Using pure 12vac on two of those pins, one is a safety ground for the metal chassis.
or...
It needs a 12vac input which is split between two of those pins, and the third pin is a center tap, so as a result the two pins actually are 6vac each.
I would imagine this thing not requiring too much current as it is merely an audio device and phone interface. We do know that rectification and filtering takes place inside. From the looks of it..the company no longer exists.
I thought your name really was RF Burns until I listened to the last Low Power Hour!
It is sort of a mind teaser! On a forum called "Repair World", an electronic technician's source for info, imagine the frenzy my net name caused there!
Just to add a bit more info on those silly multi-pin DIN power plugs. Normally the multi-pins would have different voltages on them. What throws off everything is the label on the device or power supply with only one voltage number! Then you are really in a mind twister blister!
But the engineer who designed this thing obviously jumped on the same bandwagon of odd ball power plug interfacing, which really is sort of pointless considering this thing was designed for band use, where they are not patient in regards to messing with non-standard interfacing of their gear. Raises the question as to why this company faded into silence after only 14 yrs with a product that obviously can sell to a very wide market.
Blowing up the picture...are you sure that thing has 3 pins or 4? Looks almost like it has 3 small pins arranged in a ^ pattern and below them is one larger pin, then you got the sleeve contact which if that is the case..makes this a 4 pin connector with sleeve..total 5 contacts. Oh boy!!! 😀
RFB
No, it's definitely a three pin as described in their "manual". That one larger thing you saw is just for a plastic "pin" to keep it lined up.
I had actually passed on one of these on ebay after I couldn't find any info on it anywhere except their website. Then a few weeks later I saw another one from another seller, and I reconsidered, and went ahead and bought it for about $50 because I thought it was so neat.
It appears like it's had little to no use, but the pots (? little dials) all seem pretty loose to me. - I think I should have gone with my initial gut feeling and passed this never-heard-of-before unit up... But I got it now, so..
Ahh...well I know of a few of these DIN plugs where there is a main center hole but it serves more than just a line up key-hole. Some of them will serve as the main ground return and the outer shell serves as more of an isolation shield for signal rather than a ground current return.
Well for 50 bucks you cant beat it. Considering that went for over 300 bucks new. When you say "loose" with the pots, do they wiggle in the shaft as if worn or is the rotation loose?
Looks like the best approach here is to open it up and take a close look at that power plug and foil pattern on the board and start tracing each lead to where it goes. Look for rectifier diodes or rectifier bridges. There should be a nice large filter capacitor there too.
Another thing to consider is that this may indeed need a split ac voltage input because according to the spec sheet still on the website, its got an FCC registry number for Part 15 compliance for computing devices. This thing obviously has dual rail supply on the DC side of things.. ie + and - voltage rails. Only way to get that is either through a dual split ac input to produce + and - DC rails, or it has a switching power supply inside that provides the multi-voltage rails for the DC side. It is possible it may have a DC to DC converter to supply the - voltages...but unlikely since those as well as switching supplies tend to cause problems in audio circuitry without some serious filtering and bypassing involved.
Again only real way is to crack it open and see. I tried to google some kind of schematic but no go.
Maybe if you could track down the buyer of the previous unit, and message them through the ebay message system, ask about the power supply unit and what it says on the label of that power supply itself. That may help in at least researching to fit your unit with a suitable sub power source.
RFB
Ahh...well I know of a few of these DIN plugs where there is a main center hole but it serves more than just a line up key-hole....
Well, I'm not 100% on this, I tried to look in there but can't be sure. The "wrong" pwr supply they sent me has a plastic pin there.. but mostly it's their manual on their website that says:
POWER SUPPLY. Connect the male 3-Pin mini DIN power supply plug (fig A) to the female power jack on the back of the Phone Jam labeled 12V AC. (Fig B) *MAKE THIS CONNECTION BEFORE PLUGGING THE POWER SUPPLY INTO THE WALL!
Well for 50 bucks you cant beat it. Considering that went for over 300 bucks new. When you say "loose" with the pots, do they wiggle in the shaft as if worn or is the rotation loose?
They wiggle in the shaft.. all of them do.
One things for sure, they didn't build it cheap. It's pretty heavy metal, and it looks like it was seriously built inside.
Looks like the best approach here is to open it up and take a close look at that power plug and foil pattern on the board and start tracing each lead to where it goes. Look for rectifier diodes or rectifier bridges. There should be a nice large filter capacitor there too.
It took 28 screw to get access to the power supply board! Everything had to come out. I took several pictures of the power board, it has 5 wires coming out of it which then plugs into the main circuit board.
I don't know, so I took these pictures using a cheap webcam, -- what do you think? http://end80radio.com/phone-jam-pwrsp.htm
Maybe if you could track down the buyer of the previous unit, and message them through the ebay ....
Great idea, I just stopped this post to do that..but it wasn't available, however, another seller just sold one and I emailed them.. the thing is, in this auction picture, it appears to be the exact same power supply I have, but it's not a close up and I can't be sure - but the pwr box and plug and the layout of the writing on it looks the same. http://cgi.ebay.com/Anomaly-Phone-Jam-Music-Telephone-/290539662616?pt=Music_Other_Formats&hash=item43a5836d18
I hope I didn't take this thing all apart for nothing!
But one thing is for sure, the pwr supply says
Input 120V 60hz 50W
Output: AC 28VCT 1A
and the Phone jam case itself has 12V AC clearly imprinted in white on the casing
Edit:.. In a couple of the pictures it looks like brown burn or something on the board, but there's nothing there, it's just the webcam. The insides look immaculate.
I will examine the photos. The PS input board most certainly takes a dual ac voltage input...the rectifier diodes are right behind the plug itself and there are them big ol fat filter caps. Judging by the voltage on the filter caps, 35vdc, it is safe to say that this thing takes more voltage at that plug than what is written on the case. So it may indeed use that supplied 28 volt power supply they sent with it.
If it only was meant for 12, those caps would be a bit less in their voltage ratings...16 or 20...but here we see 35.
Let me continue to examine these photos and I will get back to you.
RFB
Ok. This thing has a total of 4 voltage rails. Two are 12 volts, both + and -, and two 5 volt, + and -. I suspected as much. This requires 28VAC at the input with a center tap. So you have two pins with 12vac and the single pin is a center tap. In all...28vct.
Here is how this was determined.
As seen on the main power rectifier/filter board, we have two sets of rectifier diode sections, one for producing raw + voltage, and one for raw - voltage. They both then proceed to the filter capacitors, one for each rail of raw + and - voltage.
The next stages are the voltage regulators. You have 4 total. Two are for the 12 volt, and two are for the 5 volt. The part numbers on the voltage regulators gave it away. Each rail has a regulator for the + and - voltages, meaning this thing produces a total of 4 DC voltage rails of positive and negative voltages for the entire mess. Plus 12 volts DC, minus 12 volts DC and plus 5 volts DC and minus 5 volts DC.
Put er all back together and plug that power supply that came with it right in and you will be good to go.
Even though it took over 20 screws to tear this thing apart, its best to find out for sure than to blindly go plugging stuff in when there is no documentation.
The brown area you spoke of is most likely just from heat buildup from one of the regulators. As seen none of them are sitting on any significant heat sinking except the PC board itself. If the brown area is not of a very deep dark brown color, ignore it.
RFB
RF, I do appreciate that. I was not expecting to see all that when I opened it up.. I thought it would just be a matter of splicing a couple wires in until I saw all that stuff on the power board.
Thanks for clearing it up for me, I didn't know how to look at it.
I think you misread my comment about the brown spots on the board - There are no brown or burnt marks on the board! - it's just artifacts from my webcam. The inside looks brand spankin new.
Also, when I said the pots were all loose you asked me to clarify what I meant; I meant that they are all loose to wiggle - I got the impression you were going to make some comment about that?
Anyway, again, thanks a lot for looking over that board, it's amazing you were able to determine so much from those low quality pictures.
Now, where did I put that tiny little screw driver.....
Oh by the way.. even in these pictures on their website it clearly shows 12v input http://www.phone-jam.com/leftdocs/product_images.html
You would think they would have addressed that error somewhere!
Well I'm glad it's wrong.
I was not finished! 😀
As to the brown thing..ya I forgot you said something about the camera. No biggie.
The pots being "wiggly", that is a bit of a concern...but if you rotate them, do they feel like they are turning as if moving on a rough surface...ie not smooth? The real test will be when you power it up and run some signal through the channels and listen for crackling in the audio or break-ups along the pot's travels.
Here is a quick schematic I drew for your power supply so you can get a better idea of why that thing uses a 28vact power supply.
When the raw AC voltage is rectified through the full bridge diode rectifier from a center tapped AC transformer and connected in this manner, it produces a dual voltage source of + and -. 28vac is used so that there is plenty of head room for current capacity. This unit contains logic circuits and audio op amps and will draw quite a bit of current so the power supply has to have enough muster to power things in there. The voltage regulators...well those are pretty self explanatory.
7805 + 5v
7905 - 5
7812 + 12
7912 - 12
it's amazing you were able to determine so much from those low quality pictures.
At least the pictures did show the regulator part numbers and filter capacitor numbers clear enough to determine this is a dual rail raw/4 regulated out power supply.
RFB
Anyway, again, thanks a lot for looking over that board
Not a problem. Glad to help.
In a way..the labeling on the back of that thing is right....but only half right because it needs two 12vac in's, but yes it really should say 28vac.
Sometimes companies will do this so that if you were to go out and replace the large "wall wart" power adaptor/step down transformer (120v to 28v), and actually go by the label, it wont work too well! Its so that you have to go to the company to get the right "wall wart" !! A common trick I have see all to often..and is why I suggested opening this up to know for sure by examining the power supply board inside. 🙂
RFB
All over my head, although the schematic does simplify the general concept of it to me.
The pots being "wiggly", that is a bit of a concern...but if you rotate them, do they feel like they are turning as if moving on a rough surface...ie not smooth? The real test will be when you power it up and run some signal through the channels and listen for crackling in the audio or break-ups along the pot's travels.
All 18 of the pots wiggles, but the shafts extanding up from them are all rather long too (3/4" tall). When I turn them they feel smooth as silk, no indication at all of rubbing or grinding or anything like that, just a smooth easy rotation.
On the pictures, I had a hard time focusing it up close, I was trying to get the writing to show - it's a brand new flexible long neck webcam I got from china, it looks real cool and it was dirt cheap.. but then again so is the camera! But I'm glad it did the job.
..and is why I suggested opening this up to know for sure by examining the power supply board inside. 🙂
I'm glad you did, I was afraid to plug the thing in.
I'll put the thing back together when I get back this evening