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  #16  
Old 09-10-2016, 09:20 AM
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N2IXK N2IXK is offline
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Thanks for posting this thread, Dave!

I got a v1 EPROM from you a while back, and it works great. Will probably upgrade it to a v2 soon using the hex file you posted.
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  #17  
Old 09-10-2016, 07:26 PM
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Zenith6S321 Zenith6S321 is offline
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You're welcome, just tryin to give back a little for all the great information everybody posts here. Upgrading from V1 to V2 should be easy for you.

Dave
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  #18  
Old 12-20-2016, 06:46 PM
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OMG! Dave and whoever authorized my inclusion in the Video Karma group, you are a Godsend! My poor little 621 and RA103 have been waiting a very long time for alignment. Now you have provided the final pieces needed. I previously ordered an e-prom burner (not arrived yet), and I had resigned myself to learn how to program in C. Now, thanks to you, I can invest that time and energy into what I enjoy most: restoring these old gems. Thank you. Dan
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  #19  
Old 03-23-2017, 03:48 PM
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Well, I'm at my wit's end. I've tried and tried to burn my own eprom for my VA62 and have succeeded only in raising to blood pressure and loosing my hair. Would someone be merciful and sell me a modified eprom? I and my needy vintage sets would be eternally grateful!
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  #20  
Old 03-25-2017, 08:45 AM
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Zenith6S321 Zenith6S321 is offline
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PM sent. You might also want to look at this post:

http://videokarma.org/showthread.php?t=268392

That lets you shift newer 45.75Mhz IF sweep generators down to the lower frequencies of the older low band IFs.

Dave
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  #21  
Old 04-08-2017, 02:36 PM
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Your kind offer to see me an eProm

Dave, please forgive my long (and possibly perceived rude) delay in responding to your post to me. I'm back in the saddle again after some health challenges. I would like to move forward with my VA62 modification and would greatly appreciate version 2 of your eProm. What is a PM? Thanks for your patience. Dan
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  #22  
Old 04-08-2017, 08:11 PM
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Zenith6S321 Zenith6S321 is offline
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No problem. A "PM" stands for Private Message that this forum supports. It should pop up automatically when you login to this website. On the top right of this webpage you will see the words Private Messages highlighted in blue. Left click on those words and it will take you to the private messages sent to you (just like email). I will try also try to send you a regular email.

Dave
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  #23  
Old 11-05-2017, 09:48 PM
RayMaynard RayMaynard is offline
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Dave you have done a remarkable job on this mod. Thank You!!
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  #24  
Old 02-22-2018, 02:09 PM
dtryon dtryon is offline
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Also want to mod the VA62a

Hey Dave,
Have been reading about the Eprom modification for quite some time and I am wanting to try that on my VA62a. Would you be so kind as to PM me the info? Thanks, I can't wait to work on the Sencore.

Thanks,
Denns
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  #25  
Old 02-25-2018, 05:49 PM
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Zenith6S321 Zenith6S321 is offline
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Mod EPROM

Dennis,
PM sent. I have found that you can touch up IF alignment using the VA62A, but a set that is way out of alignment usually needs a sweep generator alignment. Lately I have been using a B&K 415 along with a down converter to heterodyne its 45.75 MHz IF down to the low frequency of old TV IFs. here is a link to a post describing that:

http://videokarma.org/showthread.php...&highlight=415

Dave
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  #26  
Old 04-02-2018, 12:14 PM
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Notimetolooz Notimetolooz is offline
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An excellent modification to the Sencore.
Very commendable work developing the mod and the wright-up.
I would add some ESD (electrostatic discharge) precautions to your posts, especially for people doing the modification during dry air conditions like the winter. One of those grounded wrist straps is a good idea, as well as working on a conductive ESD matt. The screwdriver blade you show prying the EPROM out should be in contact with your finger or grounded some other way. I think some parts of this vintage are particularly prone to damage.
Another technique I use to catch the metal fragments when drilling is to use a lump of modeling clay stuck to the back of the panel. It may leave a smudge when remove, but it will catch more.

Last edited by Notimetolooz; 04-02-2018 at 12:21 PM.
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  #27  
Old 09-14-2018, 12:57 PM
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Sparky Sparky is offline
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Neither File works

I tried both of your hex files, but neither works on the VA62.
My original Sencore VA62 EPROM 69G94-6, has the data starting at 800-FF7, while your v1 has data from 000-7FF.

All this is seen using a Minipro. All files burned to a 2732. µP for both is an Intel 8035AHL

Is there something I am missing as to why v1 doesn't work on the VA62?

Meanwhile at the same time, I am also working on an RF output dead, VA62A.
The Original VA62A EPROM 69G94-21, has its data starting at 000-9FF.
Your v1, starts at 000-7FF. Less data?

v1 works in the VA62A, however v2 does not.
v2 has data going all the way from 000 to FFF.
I didn't think that the VA62A needed the extra address line since it was a 2732.
All non functioning occurrences above, don't boot at all. Just 8888 and garbage.

Please help.

I knew I kept that UV eraser for a reason!

Last edited by Sparky; 09-14-2018 at 02:14 PM. Reason: This is'nt autocorrect!
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  #28  
Old 09-14-2018, 01:24 PM
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Sparky Sparky is offline
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Smile

I just did an edit to v1 and set its start at 800 and it works!

Here for your examination, the modified file.
Attached Files
File Type: zip va62v1mod800-FFF.zip (3.2 KB, 1 views)
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