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+--- Thread: Twin Needle SWR meter movements (/thread-786.html)
Twin Needle SWR meter movements - VK5TM - 03-05-2019
Cross posted from the VKZLQRP forum.
This may interest some - Twin Needle SWR meter movements 100uA are available on Banggood:-
https://www.banggood.com/SZ-70-Panel-Dual-SWR-Forwad-Reflected-VU-Meter-100uA-p-1247920.html?rmmds=search&cur_warehouse=CN
About $29 for 2.
Look OK for home brew jobs and may be alright for replacements in some commercial gear.
They are available on Ebay but more expensive, search for 'SZ-70 Panel Dual SWR Forwad Reflected VU Meter 100uA'
Terry VK5TM
RE: Twin Needle SWR meter movements - VK1JA - 03-05-2019
It would be interesting to see how easy it is to overlay a different scale over the face, the 10w max forward power is too low for most applications.
RE: Twin Needle SWR meter movements - VK5TM - 03-05-2019
Looking at the pictures on Banggood, the scale appears to be screwed on like regular MU45/52 meter faces, so providing the front comes off easily enough, it shouldn't be a problem to fit a new scale.
RE: Twin Needle SWR meter movements - VK1JA - 14-05-2019
Hi Terry,
I thought I'd give one a try, for the price it will get used somewhere, no doubt
They are a good size for a 2RU rack case, providing the support rails in the rack case don't get in the way.
The front comes off easily, but the scale is glued on rather than being screwed on, but there is plenty of space between the scale and needles so you could slip a new scale on top of the current one. The difficult part would be somehow transferring the current scale marks to the new scale as you can't get the old scale out, maybe.
Taking a close look at it, it may be possible to unscrew/remove the whole needle movements so you can lay the meter face flat on a photocopier
Do you know of any web sites that you can create your own scale?
Regards
Jayson
RE: Twin Needle SWR meter movements - VK5TM - 14-05-2019
That's a pain if the scale can't be removed.
The easiest technique I know about has been to scan the original scale and then use something like Paint, Photoshop or Gimp to modify the scan.
Tonne software do a free version of a meter drawing program but I've not used it http://www.tonnesoftware.com/meter.html so not sure of it's capabilities.
There are a couple of others but can't think of their names at the moment (I'll have a dig through my files to see if I can find them).
RE: Twin Needle SWR meter movements - VK6RK - 15-05-2019
Try Galva. http://www.f5bu.fr/galva-about/
Can draw almost anything with it. Comes with many examples that can be modified as needed. Bit of a steep learning curve though
I made replacement Yaesu G-5500 meter scales for 'South' stop. Turned out rather well.
RE: Twin Needle SWR meter movements - VK1JA - 15-05-2019
Thanks for the links, I'll have a look. Another project on the to do list
RE: Twin Needle SWR meter movements - VK6RK - 15-05-2019
One of the cross-needle templates:
Colours, text and scale can be easily changed.
RE: Twin Needle SWR meter movements - VK5TM - 16-05-2019
Yes, Galva was one of those I was trying to think of.
There is another free one, but for the life of me, I just can't think of what it was called.
I use Front Designer occasionally, but that is not free (although not expensive).
RE: Twin Needle SWR meter movements - VK2XAX - 13-06-2019
Or use a range switch for different power levels rather than changing the scale. I did that for my home brew SWR bridge for 630m
https://photos.app.goo.gl/vkKcx7yQA2Jmuykx9