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Author Topic: Just received my used AL-80B - Need advice; New to Amps  (Read 17524 times)
NJ1K
Member

Posts: 369




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« Reply #30 on: August 24, 2013, 01:37:16 PM »

Still sounds like TR relay or input band switch.. 
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KD2CJJ
Member

Posts: 369




Ignore
« Reply #31 on: August 24, 2013, 01:56:09 PM »

Which is the TR relay?  The one on the back or the side? I used a magnifying glass before and the connectors look mint... whats the best way to clean the contacts? I hear easily the relaying clicking during transmit...

Also... I am getting substantial power out for this issue to be there, wouldnt power be affected?

Still sounds like TR relay or input band switch.. 
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73

Mike
KD2CJJ
WD5GWY
Member

Posts: 406




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« Reply #32 on: August 24, 2013, 02:07:12 PM »

As someone else mentioned, get a crisp, clean, dollar bill and gently slide it between the relay's
contacts to clean them. A couple of passes at the most.
If you have a schematic of the amp, you can use it to locate the relay.
james
Wd5GWY
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NJ1K
Member

Posts: 369




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« Reply #33 on: August 24, 2013, 02:47:56 PM »

As GWY said, use the schematic to locate it.  It's the Transmit/Receive relay.  It's labeled RY101 in said schematic.  Just follow the RF input coax inside the amplifier to the relay.  That's the first place the RF goes once inside the chassis. 

It might plug into a socket, or it might be soldered in.  It also might have a plastic case covering it, but that's where I would investigate first.

After it leaves the TR relay, it goes to the input band switch on the input board.  It's not likely you can tell if either are giving a problem just by looking at them.  The relay contacts should be cleaned with (as said by others) a dollar bill or some other lint free paper slid between the contacts with slight pressure applied to the contacts.  The band switch can be cleaned with DE-OXIT or I have used in the past WD-40 or LPS1 when there is nothing better available.  Usually I will clean the contacts with Brake-Klean first and then apply a lubricant such as WD-40 and then work the switch back & forth through it switching range a few times.

Sometimes you can use an ohmeter to find said dirty contacts & switches.

Also, while you're following the RF path from the input to the tube, check all solder joints along the way.  Ameritron has been known to have a few loosies along the way.



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KD2CJJ
Member

Posts: 369




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« Reply #34 on: August 24, 2013, 04:11:50 PM »

Cleaned all the contacts (they look brand new under a magnifyer)...  No change... have Plate, Grid and output power but very high SWR... I suspect something on the input board OR the caps that tie t the tube are blown... im not skilled enough to test (let alone take apart without destroying) the components.. it goes in for repair.

As someone else mentioned, get a crisp, clean, dollar bill and gently slide it between the relay's
contacts to clean them. A couple of passes at the most.
If you have a schematic of the amp, you can use it to locate the relay.
james
Wd5GWY

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73

Mike
KD2CJJ
WD5GWY
Member

Posts: 406




Ignore
« Reply #35 on: August 24, 2013, 04:36:07 PM »

Cleaned all the contacts (they look brand new under a magnifyer)...  No change... have Plate, Grid and output power but very high SWR... I suspect something on the input board OR the caps that tie t the tube are blown... im not skilled enough to test (let alone take apart without destroying) the components.. it goes in for repair.


That is probably the wisest thing to do once you have done all you feel comfortable
trying to do. It's too easy to get a nasty shock or worse, when digging around in an
amplifier. Good luck and once you get your amp back, you should get many years of
use out of it, the AL-80b is a good, dependable amp.
james
WD5GWY
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K7KBN
Member

Posts: 2840




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« Reply #36 on: August 24, 2013, 06:36:01 PM »

You mentioned the "pots" (which WIK correctly identified as the adjustable input tuning coils), but I haven't seen any mention of your having tried to adjust them.  Takes a special 0.1" NON-METALLIC hex tool (similar to an Allen wrench), but made of plastic.  Ameritron/MFJ sells them.  The procedure might be in the operating manual; not sure for the AL-80B.  They should be able to email the procedure to you.
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73
Pat K7KBN
CWO4 USNR Ret.
WX7G
Member

Posts: 6332




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« Reply #37 on: August 24, 2013, 07:44:37 PM »

Every band exhibits a high VSWR and it's unlikely that the previous owner detuned the input coils on every band. It is likely that something common to all bands has failed. Trying to tune the input coils is not the solution and will only make the final fix more difficult.
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W5ER
Member

Posts: 74




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« Reply #38 on: August 25, 2013, 02:45:54 AM »

Give Ameritron another call, inquire if you might possibily EXTEND the warranty for another year.  I did and they did, kind of recall the cosy being less than $70. 

I then was able to return it for repair, under warranty of course, only had to pay shipping one way, which was way more than the cost of the extension. 

Nice people once one gets past the phone answerer, had a very rough time getting my feeble brain to understand the seemingly alien language she was using.
GUD LUCK
Ed
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KD2CJJ
Member

Posts: 369




Ignore
« Reply #39 on: August 25, 2013, 05:27:51 AM »

Excellent advice..I bought it used and it is out of original warrantee.  I will try what you suggested but if I can't I see I will have the option to purchase a warrantee even though I purchased it used.  I will explore both.

Also want to thank the Dave's outside Dayton for going over my procedures and troubleshooting with me over IRLP.  Unfortunately we all came to the same conclusion it needs to go back for repair.

Give Ameritron another call, inquire if you might possibily EXTEND the warranty for another year.  I did and they did, kind of recall the cosy being less than $70. 

I then was able to return it for repair, under warranty of course, only had to pay shipping one way, which was way more than the cost of the extension. 

Nice people once one gets past the phone answerer, had a very rough time getting my feeble brain to understand the seemingly alien language she was using.
GUD LUCK
Ed
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73

Mike
KD2CJJ
WX7G
Member

Posts: 6332




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« Reply #40 on: August 25, 2013, 09:28:06 AM »

An extended warranty applies to failures that occur after the extended warranty goes into effect. it does not cover failures that have already occurred.

This is specifically called out in two places in the Ameritron Extended warranty:

"The extended warranty warrants to the purchaser that if the product should fail during the agreed term, Ameritron has the option to repair or replace part(s) (except tube and output transistors) and provide necessary labor free of charge".

[the agreed term means after the extended warranty goes into effect]

"If your Ameritron Product was purchased used or is out of its original warranty: The Ameritron product will need to be sent to Ameritron's production facility pre-paid shipping for evaluation. The owner agrees to pay for return shipping charges, necessary parts and labor to put the product back to the original Ameritron specifications. Ameritron has the right to not provide an Extended Warranty Plan."

[this means that Ameritron will first bring the unit up to spec at your cost then they may begin an extended warranty that covers failures after this point in time]
« Last Edit: August 25, 2013, 09:30:24 AM by WX7G » Logged
AH6RR
Member

Posts: 803




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« Reply #41 on: August 26, 2013, 01:09:28 AM »

I still say it is one of 3 things.

1. The Caps that couple the RF to the Filament choke.
2. The Filament Choke has a bad solder joint or is broken.
3. If it was shipped with the tube installed then the tube socket could be bad.

Or you have it hooked up backwards input on the output ect. Another thing could be is that the T/R Relay was 
knock out of alinement during shipping. The T/R relay is mounted to the board where the transformer wires are connected to.
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N8XI
Member

Posts: 157




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« Reply #42 on: August 26, 2013, 07:09:56 AM »

Mike,

Looks like you have checked several things.
I looked at the schematic for my AL-80B and there is the Band Switch
which selects the High-Pass filters for each band.
I had a case where the switch wasn't making for 15/17 and the AUX position.
I didn't have high SWR but could not get much output on 15/17 or 10/12.

Now, I don't know how possible this is, but if you are having high SWR between the Rig and Amp,
maybe the Switch S-201C and S-201D are out of alignment?

73, Rick - N8XI
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KD2CJJ
Member

Posts: 369




Ignore
« Reply #43 on: August 26, 2013, 08:00:57 AM »

I looked over the tube socket and the filament choke... they both look good.

I decided to run another test while I hear back from Ameritron on shipping instructions.

If I flip the band switch to the 15/17 but keep the rig set to 20 meters, SWR drops to a 2.1 and with applied power (about 50 watts drive) it drops to a 1.7 compared to a 4.5:1 SWR when the amps band switch is on 20 meters and the rig is set to 20 meters.

 After conversing with a friend who just got back from vacation (he has rebuilt SB200s and Kenwood amps) he believes its the input band switch may be out of alignment based on the feedback above.  I will spend more time on the input bandswitch (back of the amp) and see if I can see anything going on in there... He said it may have come out of alignment (bad luck) if the set screw (if there is one) came off, etc OR if one of the little tabed contacts broke off. He highly doubts any of the caps are broken (but possible).

Does anyone have any advice on properly aligning the rear band switch (knowing what position for each band)?  Could someone take a picture of just 1 band and send this to me to validate the position?




I still say it is one of 3 things.

1. The Caps that couple the RF to the Filament choke.
2. The Filament Choke has a bad solder joint or is broken.
3. If it was shipped with the tube installed then the tube socket could be bad.

Or you have it hooked up backwards input on the output ect. Another thing could be is that the T/R Relay was 
knock out of alinement during shipping. The T/R relay is mounted to the board where the transformer wires are connected to.
Logged

73

Mike
KD2CJJ
KD2CJJ
Member

Posts: 369




Ignore
« Reply #44 on: August 26, 2013, 08:04:15 AM »

LOL.... I was just typing my note when you submitted... My friend came to the same conclusion...  Any suggestion on how to validates its alignment?

Mike,

Looks like you have checked several things.
I looked at the schematic for my AL-80B and there is the Band Switch
which selects the High-Pass filters for each band.
I had a case where the switch wasn't making for 15/17 and the AUX position.
I didn't have high SWR but could not get much output on 15/17 or 10/12.

Now, I don't know how possible this is, but if you are having high SWR between the Rig and Amp,
maybe the Switch S-201C and S-201D are out of alignment?

73, Rick - N8XI
Logged

73

Mike
KD2CJJ
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