[TenTec] Ten tec omni 6+ (5 mhz PLL board)

[k8mp at aol.com]

 Hi Mike,
Here's my final synopsis. There's more here than you'll probably ever need to know. By the way, the info is also on the reflector from back in '09 when I had the problem.?
http://lists.contesting.com/archives//html/TenTec/2009-10/msg00238.html


I suggest you compare my symptoms to what you're rig is doing and
if it's the same (or very similar), just go for the?jugular and hit ALL the connections on the 5 mhz PLL board.?


Later, Joe


Radio Dudes: I figured I'd give you a final (I hope) synopsis on the PLL/Synthesizer  problems I dealt with recently. The info may come in handy for someone, some  day. By the way, thanks to those who steered me towards the PLL board.  Otherwise, my radio might still be broken. (or in Sevierville) Symptoms:The display reads correctly. It even changes when you turn the VFO.  However, the received freq doesn't change. How did I know that?   When I changed bands to 160, I could hear an AM broadcast station.  Turning the VFO didn't change what I was hearing. Fixing it:It was suggested that I check the 5 to 5.5 Mhz output from the PLL. I  didn't have a freq counter, so I used a Tektronix 456B, which is a 200 Mhz  scope. The output showed as 5.8 Mhz and it did not change when cranking the VFO  or hitting the up/down buttons.   The 2 inputs to the board (10  Mhz clock and serial freq data) appeared to be good,  so I  was pretty sure I was on the right track.  NOTE: The output also had what seemed like a low voltage level (1 volt  p/p). I called Ten Tec about the sig level, but they didn't know what it should  be. (More on that later) Another Ham who had PLL board problems strongly suggested that I  re-heat suspect connections on the board. I did this (in fact, I  hit every connection on the board) and the radio worked for 2  days. While it was in the working state, I scoped the PLL output and saw it  change with the up/down buttons. The voltage level was 1 volt p/p in the working  state, so I now knew that was correct. For the next few days, the radio would work then not work. I tried to "make  it fail" with heat and cold, but those didn't seem to make a difference. During  this process, I made a few notes and drawings of various waveforms and  levels around the board. Unfortunately, 3 weeks have passed and some  of those notes don't make any sense to me now. Here are the ones that  do: 1) At the junction labeled "Test point" (duh...go figure) on the PLL  schematic: When working, and the rig set to 40 meters, it had a 100 mv  sine wave riding on a 325  mv DC level. (I forgot to record the  freq).  When failing, it was nearly at ground potential (less than 15 mv),  with no sine wave. 2) At U4, pin 5, with the rig working, I saw 775 mv when on 40  meters. I didn't record it in a failed state. 3) At R11 and R12, with the rig working: You should see a 5 volt level,  with negative-going spikes to ground, every 100 usec. 4) U5, pin 6, with the rig working: 133 Mhz signal. I can't remember if it  was square or sine. 5) U4, pin 7, with the rig working: 2 v DC 6) U4, pin 1, with the rig working: 3.5 v DC "Sometimes it's better to be lucky than good" While beating on components to try make it work, I noticed that a  slight tap on L12 could make the rig fail or work. I re-heated the connections  to L12, (including L12's case to ground on top of the board) and the  radio has been fine since. That was over 2 weeks ago. I even got brave enough to  put it all back together several days ago and it's still working.  Hopefully, it's been put to bed. Later,  Joe 


-----Original Message-----
From: Mike <w4mjr at att.net>
To: k8mp <k8mp at aol.com>
Sent: Wed, Nov 11, 2015 8:48 pm
Subject: Re: Ten tec omni 6+

  OK Joe that would be great. I like my 564 and miss it when not in use. I moved the Hercules II over to my ICOM 751A for the time being.? Ok Joe look forward to your repair info. Thanks agn. Mike W4MJR
 Sent from my ALCATEL ONETOUCH A564C
 On Nov 11, 2015 7:33 PM, k8mp at aol.com wrote:  You jogged my brain and yes, that was me Mike. I fixed it myself with help from the guys on the Ten Tec reflector.     
       It involved removing one of the boards (PLL board, think) and re-heating EVERY connection (top and bottom) with an iron (and add new solder if necessary)   
       
         I'll look over my notes and get back to you with the details, probably tomorrow.    
         Later, Joe    
         
Sent from AOL Mobile Mail     
     
     
-----Original Message-----     
From: Mike <w4mjr at att.net>     
To: k8mp <k8mp at aol.com>     
Sent: Wed, Nov 11, 2015 07:36 PM     
Subject: Re: Ten tec omni 6+     
     
     
      602606e"              Sorry Joe but I might have you mixed up for someone else. I have a ten tec omni 6 plus and started losing audio sound. It would come back in and then go back out. I could put it on the 160 meter band and hear an AM station but could not make it out what they were saying.? I replaced the 3 volt battery backup and did a reset but nothing changed. Anyway Joe I have been reading so much about trying to figure out what was wrong before I send it in to ten tec for repair.? Anyway I thought I had read on the contesting.com about you and your omni 6 plus. I know it had to be an old thread. I just didn't pay any attention to the date. If I have you mixed with someone else problem I appolize.?????????????? Thanks, mike w4mjr
        Sent from my ALCATEL ONETOUCH A564C
                On Nov 11, 2015 5:14 PM,         k8mp at aol.com wrote:        
                  Hi Mike,                     Can you refresh my memory by pasting the details into an email?          
                     Thanks, Joe           
           
Sent from AOL Mobile Mail           
           
           
-----Original Message-----           
From: Mike <          w4mjr at att.net>           
To: k8mp <          k8mp at aol.com>           
Sent: Wed, Nov 11, 2015 12:46 PM           
Subject: Ten tec omni 6+           
           
           
                       Joe I am having the same problem with me 6+ as you had with losing the audio. This might be old stuff because I was just searching thru the web and saw where you were looking for answer about your rig. Did you get yours repaired and what was the cause.? Thanks, Mike w4mjr  Sent from my ALCATEL ONETOUCH A564C