Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: What Does UB mean on the Front Panel of a Solid State Amp  (Read 2284 times)
K2ACB
Member

Posts: 64




Ignore
« on: January 05, 2012, 04:16:15 PM »

I have had a Tokyo Hy Power HL2KFX solid state aamplifier for over 6 years. The amp Uses 8 MRF150 FET's. It is no longer in production by Tokyo Hy Power.

Until now the amp has been trouble free. All of a sudden I was using the amp yesterday when a red led on the front panel of the amp went on. Under the led it said UB. That had never occurred before. When that occurred the amp also stopped functioning. The amp still lit up but there was no output.

I immediately took out the manual. It said UB means unbalanced and the amp probably will need repair.


I would like to know what they mean by unbalanced.The manual said nothing more about this.  Could this be a major repair? Could this mean one or more of the FET's went bad?Could it be in the power supply or transformer?

If anybody has any comments I would appreciate it.

73
Alan-K2ACB
Logged
M0HCN
Member

Posts: 473




Ignore
« Reply #1 on: January 05, 2012, 05:46:01 PM »

It means that the power combiner is seeing unequal output from the PA blocks, one of them has gone faulty or is not getting power or drive.
It could be power, it could be bias, it could be a blown FET or two.

Could be minor, is likely to be pretty major.

Regards, Dan.
Logged
VE1IDX
Member

Posts: 141




Ignore
« Reply #2 on: January 05, 2012, 07:38:38 PM »

UB = Uber-Blown  Roll Eyes

The previous poster is correct. The combiner is seeing an unbalance caused by unequal power output from the modules for a variety of reasons. It may be minor but usually isn't.
Logged
TANAKASAN
Member

Posts: 933




Ignore
« Reply #3 on: January 08, 2012, 03:14:16 AM »

It should be possible to get this amp working again. Even though only one FET may be blown you will probably find that the amplifier is configured to use four pairs, and so it will be better to purchase and fit a pair of MRF150 devices to the affected module.

Tanakasan
Logged
K7KBN
Member

Posts: 2766




Ignore
« Reply #4 on: January 08, 2012, 10:32:26 AM »

Stands for "Uuuu... [pronounced OOOoooh]...Boy  This is gonna be expensive!"
Logged

73
Pat K7KBN
CWO4 USNR Ret.
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!