vladxmxr
Newbie
Dear friends,
As a proud owner of a Canon 7s, I have experienced the problem associated with metering voltage on these wonderful devices.
Searching the net far and wide, I have come across this forum and some posts by a user called "John Neal" who said he made better and more affordable versions of the CRIS MR-9 adapter.
Unfortunately, these posts are quite old and I have yet to find out how to contact this user.
My questions are the following:
Did anyone here order an adapter from this user and does anyone have his contacts?
As a proud owner of a Canon 7s, I have experienced the problem associated with metering voltage on these wonderful devices.
Searching the net far and wide, I have come across this forum and some posts by a user called "John Neal" who said he made better and more affordable versions of the CRIS MR-9 adapter.
Unfortunately, these posts are quite old and I have yet to find out how to contact this user.
My questions are the following:
Did anyone here order an adapter from this user and does anyone have his contacts?
shimokita
白黒
John Neal's user account is still valid here at RFF and his last post was one year ago... did you try sending him a PM or email as per his user profile?
Casey
Casey
vladxmxr
Newbie
Thank you for pointing out to me that there is a PM and an e-mail function on this forum. I honestly don't know how I missed it, maybe it's time I get some glasses.
I have contacted John and I hope he still makes the said battery adapters.
shimokita
白黒
Let us know how it works out for you...
Goody
Established
For what it's worth I have had the CHRIS MR9 adapter in an Olympus SLR for years and it works very well. There are various internal conversions using a similar diode for the OM 1 - they are probably adaptable to the 7, if you are so inclined. Basically it's just soldering the diode between the battery feed and metering circuit - requires removing the bottom plate of the camera.
Robert Lai
Well-known
For about $20, you can get the pradethai adapter from Thailand on ebay.
It was Gus Lazzari that first informed me about these great adapters. They are even gold plated for maximum conductivity.
I use these exclusively now (even in my Canon 7s), with no problems.
It was Gus Lazzari that first informed me about these great adapters. They are even gold plated for maximum conductivity.
I use these exclusively now (even in my Canon 7s), with no problems.
vladxmxr
Newbie
Thanks, as there was no reply from John Neal, I ordered one of these.
Are you using yours with a silver oxide battery or an alkaline one?
Goody
Established
I believe that they are meant to be used with silver ox battery as the voltage is more consistent then the alkiline batteries. I believe the mercury batteries are the most consistent -- that's why they were originally speced.
Larry Cloetta
Veteran
Saw this thread 3 weeks ago, and ordered one of these pradethai adapters, which arrived yesterday. Sounded like a great idea, and much less expensive than the Kanto one, pretty too.
Problem is, I just checked the through voltage on mine, with the recommended 386 battery, and it is delivering 1.52V, not the 1.35V for which it is sold.
I was wondering if others had actually checked the voltage this pradethai adapter was delivering, with a voltmeter, or just put it in the camera and assumed it was working (?). Perhaps I just got a broken one, but would be curious to know if others had actually checked theirs before using it.
It's pretty, though!
sevo
Fokutorendaburando
That may be a lack of load. I have Kanto adapters, which also are 1.52V when checked with a modern digital voltmeter. With a analogue meter, the voltage drops to below 1.4V.
rfaspen
[insert pithy phrase here]
Ahhh. What are the chances you checked voltage with a digital voltmeter?
Try checking with an analog voltmeter, or place a load in the circuit.
I know this because I also ordered one of the pradethai adapters, put the AgOx battery in it and checked with my digital voltmeter. It read 1.55v I was seriously bummed and didn't use the thing. Some time later, I found a thread somewhere about these exact adapters and this issue with the digital voltmeter was discussed. I dug out my analog voltmeter, and !bueno! it read 1.35v which I wanted.
Now, even though it gives correct voltage under load, I still have incorrect readings in my Leica CL. The meter is .....off. My Gossen SuperPiolot SBC apparently works with either the old Hg batteries or new AgOx (1.5v) batteries. So, no need for the adapter there. Sorry, I'm off on a tangent now...
Try checking with an analog voltmeter, or place a load in the circuit.
I know this because I also ordered one of the pradethai adapters, put the AgOx battery in it and checked with my digital voltmeter. It read 1.55v I was seriously bummed and didn't use the thing. Some time later, I found a thread somewhere about these exact adapters and this issue with the digital voltmeter was discussed. I dug out my analog voltmeter, and !bueno! it read 1.35v which I wanted.
Now, even though it gives correct voltage under load, I still have incorrect readings in my Leica CL. The meter is .....off. My Gossen SuperPiolot SBC apparently works with either the old Hg batteries or new AgOx (1.5v) batteries. So, no need for the adapter there. Sorry, I'm off on a tangent now...
Larry Cloetta
Veteran
Chances are very good!
Many thanks for the correction, both of you. Sad to say, I have three digital multitesters, and nothing in the way of analog except LPs and film. More than happy to take your word for it however, until I get one.
Also measured my 5 week old Wein cell, with the same meter, and it's showing 1.11V, at best. Ah, well.
Many thanks for the help!
wolves3012
Veteran
Chances are very good!
Many thanks for the correction, both of you. Sad to say, I have three digital multitesters, and nothing in the way of analog except LPs and film. More than happy to take your word for it however, until I get one.
Also measured my 5 week old Wein cell, with the same meter, and it's showing 1.11V, at best. Ah, well.
Many thanks for the help!
You can't measure the output by simply connecting a DVM to it. The adapter works by having a Shottky diode in series with the cell, which "loses" 0.15V when it's passing some current. A DVM draws almost no current at all, so gives a false reading. If you want an accurate reading, you need to measure the output with the meter circuit active, i.e. connected up and functioning - which is not easy to do!