I have been using the SPE Expert 1K-FA HF/50 Mhz mosfet linear amplifier for quite a few years. It is a a very intelligent piece of equipment, technologically advanced, with great capabilities and superb performance.
As you may already know, I am a keen contester, and 1K-FA has taken part with me in many many contests, with no signs of tear or wear.
However, since past winter, a problem came up with it, some of its front panel keys stopped operating. Since those not working were the most vital ones (ON/OFF/POWER/DISPLAY/OPERATE), I decided to contact SPE for technical advice. I only did that lately, because I mostly remote control the amplifier and all its functions through its software.
SPE`s customer support team is really prepared to face and give solution to virtually any problem that may come up with their products.
The explanation I was given for the fault, was that a specific point of the flat cable membrane that goes from the front panel to the CPU board, is constantly in touch with the left metallic chassis of the amp, and that causes a few cable lines to break as temperature rises progressively. A broken line, of course, means loss of some keys control.
I ordered a new front panel keyboard replacement, with a very low cost indeed (!), which arrived a few days later. In the envelope, there was also a piece of velcro to put between the new flat cable membrane and the point where it comes in contact with the left metallic chassis.
As you may already know, I am a keen contester, and 1K-FA has taken part with me in many many contests, with no signs of tear or wear.
However, since past winter, a problem came up with it, some of its front panel keys stopped operating. Since those not working were the most vital ones (ON/OFF/POWER/DISPLAY/OPERATE), I decided to contact SPE for technical advice. I only did that lately, because I mostly remote control the amplifier and all its functions through its software.
SPE`s customer support team is really prepared to face and give solution to virtually any problem that may come up with their products.
The explanation I was given for the fault, was that a specific point of the flat cable membrane that goes from the front panel to the CPU board, is constantly in touch with the left metallic chassis of the amp, and that causes a few cable lines to break as temperature rises progressively. A broken line, of course, means loss of some keys control.
I ordered a new front panel keyboard replacement, with a very low cost indeed (!), which arrived a few days later. In the envelope, there was also a piece of velcro to put between the new flat cable membrane and the point where it comes in contact with the left metallic chassis.
LET THE OPERATION BEGIN, THEN !!
After having removed top and bottom cabinets, I removed the front air filter to make the front panel extraction easier.
Front panel removed and unplugged from the main body of the amp. Although cabling connectors are very difficult to mix, it is better to take note (or a photo) of which cable of the main body goes to which connector of the front panel. It will save you from unneeded trouble !!
Also, note at the left part of the front panel, the flat cable membrane that connects the front panel keyboard with the CPU board ... that is the cause of the fault !!
Several visible cracks amongst the cable lines of the membrane !! AHA !!
A better view of several of the cracked cable lines on the membrane.
The flat cable membrane end towards the CPU board ... looks like it needed a replacement, after all !!
Before accessing the keyboard, the CPU board has to be separated from the front panel. This is easily done by removing a few cables and four spacers.
Faulty keyboard removed from the front panel. Easily done with the help of a sharp knife, to cut through the powerful 3M glue used to stick the keyboard to the metallic chassis of the front panel. The LCD protective glass was cleaned with pure alcohol and a soft cloth to remove all remaining glue residues.
New keyboard placed on the front panel. Take great care in aligning both the four corners of the keyboard membrane, as well as the six small rectangular LED holes. Doing that right will help you later on when you will put the amp together again.
Here you may see the self-adhesive piece of Velcro, which I put between the keyboard flat cable membrane and the left side metallic chassis of the amp. From now on, chassis temperature will not affect this membrane.
Time for testing after repair ... Amp is back in business !!
100% success in this one.
I have to thank for their valuable help and technical notes Mr. Guido Pandolfi of SPE and Bob, W5UQ of Expert Amps USA.
Summary of repair:
Cost of keyboard: €10
Cost of shipping for keyboard: €6
Time of repair: 60 minutes, including unmounting and mounting the amp from/to the shack cabinets.
Result: All keyboard functions restored.
7 comments:
Thanks...my Amplifier has the same Problem now....i contact SPE for the replacement Keyboard.....
73 Walter
HB9EOT
Well done OM.
Unfortunately, I have the same problem. I just bought this awesome amp a week ago. It is still cosmetically like new. Please be so kind as to send me an email address so I would be able to order this front panel. Unfortunately, I live in South Africa and guess this would take some time to get to me. My email address is jacqueszs1wc@gmail.com
73's
ZS1WC Jacques
Loved rreading this thanks
This instructions make it sound as a simple, with some care, project....doable by anyone.
My issue is that the amp will turn on by itself after a few minutes of I shut down via software control...I seldom touch the front panel...to me, it appears that with time, the main ribbon cracks due to heat. This is probably why they provide velcro to place in between.
I have contacted SPE in Italy and they point to the front panel keyboard...it needs to be replaced. Our USA rep has gone through a new company (Vibroplex) and they don't have any parts in stock yet ...the cost of the front panel is what 10 pounds and shipping 6...that is so a bargain.
I don't mind placing the order from Italy or Australia.
Rafael / NN3RP
I don't have a problem with the front panel keyboard. I have another problem with my SPE Expert 1.5K FA (Series II). The digital display goes on normally on first power up, but once I start putting RF through, the display goes totally blank (no information, just bright white backlight). I have tried putting ferrite chokes on all coax lines goes into the amp, along with the power cord, but problem still is occurring. The amplifer does work as far as putting correct power output, but I have no information visible on display. Turning off the amp, then back on will reset the display to normal. Anyone have this issue? Suggestions?
Thanks,
Bob K3AC
I see this as a *design issue* with this amplifier. I also had to purchase the keypad with ribbon cable to resolve the issue. I was charged $50 USD for it which I really shouldn't had to pay since it is clearly a design issue.
Note: The velcro did not come with my replacement, only the keypad and ribbon cable. So I also found and used a piece of velcro to keep the cable from contacting the chassis.
The repair is easy enough done, just be careful along the way and take your time.
73! de Nick K9XN
Great read thank yyou
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