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It seems that the FT-818 group is exhausted, so I try here.
My 818 has no output on 2 m, while it works on 70cm and HF. The SWR is at maximum, so I think some relay is not closing when it should.
Is there any way to have the diagrams and the component layout plan of the 818?
?
Thanks to all
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Pietro I2OIM
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Pietro? I2OIM
I have a PDF of the 817 / 817ND? if these would help I can send a copy
Charlie KA9HDG
On Thursday, September 19, 2024 at 10:57:03 AM EDT, Pietro Molina <pietro@...> wrote:
It seems that the FT-818 group is exhausted, so I try here.
My 818 has no output on 2 m, while it works on 70cm and HF. The SWR is at maximum, so I think some relay is not closing when it should.
Is there any way to have the diagrams and the component layout plan of the 818?
?
Thanks to all
?
Pietro I2OIM
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Hi if you look up posts from me 2E0DMB you will find the info, I had this problem with a ft817nd and it was a diode? On the bottom of the band switching board if I remember?correctly This has been common lately, Dave 2E0DMB?
It seems that the FT-818 group is exhausted, so I try here.
My 818 has no output on 2 m, while it works on 70cm and HF. The SWR is at maximum, so I think some relay is not closing when it should.
Is there any way to have the diagrams and the component layout plan of the 818?
?
Thanks to all
?
Pietro I2OIM
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Hi This is my post when i found the problem i was having,
Hi i found this when my FT817 did not output power on 2m and it was the Diode that had gone bad,
Good Luck, Dave 2E0DMB
so on Pin 8 of Q3003 on the PA Unit is a voltage called V-TX that
switches the output of the PA FINAL thru to the 2 Meter Low Pass Filter.
There it passes thru the Relay RL3001 which for 2Meter is closed from the
moving contact to the Normally Closed (Black) contact which passes the TX
energy on to the Diode D3003 an HSU277 ( Pin Diode ) and from there on to
the ?front or rear Antenna select RL3015.
Other than that, there is another Diode D3005, that enjoys going bad and it
can also cause the problem you are having.
These are both on the bottom (B side) of the PCB. ?This diode turns on to
protect the RX when TXing. ?This is turned on from pin 4 on the Q3003.
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With those symptoms, ?are likely to have an open D3003. It's possible it could be a relay connection or bad solder joint to a coil in the same place. But, D3003 is the usual issue. ?One test is to check the current draw on 2M. ?If you're still drawing the same current on 2M FM as 70 cm, the signal is getting to the final transistors, but not getting out of the radio.
?
D3003 is on the back of the PA board, and is very tiny. ?It is a common problem. ?Here are some relevant diagrams. You can find the service manual online many places.
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?
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Hi, Is there a reliable seller for the?HSU277?
With those symptoms, ?are likely to have an open D3003. It's possible it could be a relay connection or bad solder joint to a coil in the same place. But, D3003 is the usual issue.? One test is to check the current draw on 2M.? If you're still drawing the same current on 2M FM as 70 cm, the signal is getting to the final transistors, but not getting out of the radio.
?
D3003 is on the back of the PA board, and is very tiny.? It is a common problem.? Here are some relevant diagrams. You can find the service manual online many places.
?
?
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Yaesu, maybe
I had a old radio I removed it from
Have a look for a equivalent, it's probably nothing special,but as it is on the underside of the board , I would get the correct one or equivalent ,
Good luck take your time as it is very small and fit it the correct way round, it is hard to see the white stripe, so use a meter,
Dave 2E0DMB
Hi, Is there a reliable seller for the?HSU277?
With those symptoms, ?are likely to have an open D3003. It's possible it could be a relay connection or bad solder joint to a coil in the same place. But, D3003 is the usual issue.? One test is to check the current draw on 2M.? If you're still drawing the same current on 2M FM as 70 cm, the signal is getting to the final transistors, but not getting out of the radio.
?
D3003 is on the back of the PA board, and is very tiny.? It is a common problem.? Here are some relevant diagrams. You can find the service manual online many places.
?
?
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Where to get an HSU277??
I have never had good luck contacting Yaesu support. ?I was calling during COVID, so that might have been the issue. They might have some.
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The HSU277 is very tiny, and I suspect that most people without SMD equipment and experience need two or three to finally do it correctly. In the case of D3003, the PA board needs to be removed to get at it, so the service person can position it under a magnifier. The advantage of a component replacement is that no alignment of a new board should be needed (with very careful handling). Good practice indicates a realignment when an RF board with tunable components is removed and replaced.?
There are a few suppliers that are reputable, like LittleDiode, that want about 12 Euro each for individual items. There might be reasonably equivalent PIN diodes that aren't SMD, or a different SMD form factor with similar specs, that could be retrofitted. ?It's VHF, so the signal path needs to be short. I haven't looked into it. I have a couple 30-year-old VHF amps that use standard PIN diodes, so they're around.?
I have ordered a package of HSU277s from AliExpress for about $10, hoping that they are real--or real enough. EBay has some "refurbished" items for about $10 each. I think "refurbished" means scavenged from boards. I have not had good luck in general with parts from these sources. There are lots of counterfeits that will test OK and operate well enough if they are not pushed very hard. In this case, you're putting 5 watts through the part, so you're at the edge of its capability.?
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Jim
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Thanks Jim,
The size looks like something between 1206 or 0805, perhaps 2512 metric according to a datasheet I've found. Tiny yes, but workable under a desk magnifier or microscope. I've worked on 6 pin devices about half the size so the real challenge for me will be finding suitable replacements.
Where to get an HSU277??
I have never had good luck contacting Yaesu support.? I was calling during COVID, so that might have been the issue. They might have some.
?
The HSU277 is very tiny, and I suspect that most people without SMD equipment and experience need two or three to finally do it correctly. In the case of D3003, the PA board needs to be removed to get at it, so the service person can position it under a magnifier. The advantage of a component replacement is that no alignment of a new board should be needed (with very careful handling). Good practice indicates a realignment when an RF board with tunable components is removed and replaced.?
There are a few suppliers that are reputable, like LittleDiode, that want about 12 Euro each for individual items. There might be reasonably equivalent PIN diodes that aren't SMD, or a different SMD form factor with similar specs, that could be retrofitted.? It's VHF, so the signal path needs to be short. I haven't looked into it. I have a couple 30-year-old VHF amps that use standard PIN diodes, so they're around.?
I have ordered a package of HSU277s from AliExpress for about $10, hoping that they are real--or real enough. EBay has some "refurbished" items for about $10 each. I think "refurbished" means scavenged from boards. I have not had good luck in general with parts from these sources. There are lots of counterfeits that will test OK and operate well enough if they are not pushed very hard. In this case, you're putting 5 watts through the part, so you're at the edge of its capability.?
?
Jim
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Not too unexpectedly, the HSU277 diodes did not arrive from AliExpress. Thus, I have no update on whether my lack of UHF is due to a bad PIN diode. ?
I was warned that I'd probably not receive my order from AliExpress, and then I'd be stonewalled on a refund. That is exactly what has happened. USPS, as the last-mile shipper, reports that there's no postage on the item, which is supposedly in Chicago, so they're not going to handle it. ?I should have listened.?
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I’ll bet it unexpectedly shows up. Mike Davis WA1MAD
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On Oct 11, 2024, at 1:30?PM, James Todd via groups.io <toddjam@...> wrote:
? Not too unexpectedly, the HSU277 diodes did not arrive from AliExpress. Thus, I have no update on whether my lack of UHF is due to a bad PIN diode. ?
I was warned that I'd probably not receive my order from AliExpress, and then I'd be stonewalled on a refund. That is exactly what has happened. USPS, as the last-mile shipper, reports that there's no postage on the item, which is supposedly in Chicago, so they're not going to handle it. ?I should have listened.?
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I agree. It's just hung up on the way. I do most of my business with eBay dealers. Hardly ever a problem.
On Fri, Oct 11, 2024 at 2:06 PM, Michael Davis via groups.io <maddmd818@...> wrote: I’ll bet it unexpectedly shows up. Mike Davis WA1MAD On Oct 11, 2024, at 1:30?PM, James Todd via groups.io <toddjam@...> wrote:
? Not too unexpectedly, the HSU277 diodes did not arrive from AliExpress. Thus, I have no update on whether my lack of UHF is due to a bad PIN diode. ?
I was warned that I'd probably not receive my order from AliExpress, and then I'd be stonewalled on a refund. That is exactly what has happened. USPS, as the last-mile shipper, reports that there's no postage on the item, which is supposedly in Chicago, so they're not going to handle it. ?I should have listened.?
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It's not eBay, but AliExpress. ??
The word I got was that it's a shipping scam. The individual vendor shorts the postage, and then expects USPS to deliver it anyway, collecting the postage due. USPS tracking says they're not accepting the package for shipment. ?I've had this happen a few times. When it's from an individual, and just a bit short, I get a note in my mailbox to come and pay. ?The Chinese packages are a different story.?
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Oh, OK. I get the USPS scam emails all the time. I'm waiting for an Ali Express delivery of my battery pack kit. ETA Dec 14
Mike Davis WA1MAD
(h) 781 545-4381
(c) 617 909-5103
On 10/11/2024 4:03 PM CDT James Todd <toddjam@...> wrote:
?
?
It's not eBay, but AliExpress. ??
The word I got was that it's a shipping scam. The individual vendor shorts the postage, and then expects USPS to deliver it anyway, collecting the postage due. USPS tracking says they're not accepting the package for shipment. ?I've had this happen a few times. When it's from an individual, and just a bit short, I get a note in my mailbox to come and pay. ?The Chinese packages are a different story.?
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I just ordered a battery pack from Windcamp’s official store on Aliexpress. Purchased yesterday. Projected arrival is Dec 16th. I have purchased a lot of radio bits and bobs off of Ali in the past few years. The only thing that I had trouble with shipping on is a 24v battery. The seller probably shorted the postage but no way to know that. I filed a non delivered item claim with Ali (after exchanging messages with the seller a few times) Ali was prompt with their investigation and promptly refunded me. They do pretty well. I had also ordered a few other things in the past that ended up being poor quality junk. They refunded those easily too.?
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On Oct 11, 2024, at 15:37, Michael Davis via groups.io <maddmd818@...> wrote:
?
Oh, OK. I get the USPS scam emails all the time. I'm waiting for an Ali Express delivery of my battery pack kit. ETA Dec 14
Mike Davis WA1MAD
(h) 781 545-4381
(c) 617 909-5103
On 10/11/2024 4:03 PM CDT James Todd <toddjam@...> wrote:
?
?
It's not eBay, but AliExpress. ??
The word I got was that it's a shipping scam. The individual vendor shorts the postage, and then expects USPS to deliver it anyway, collecting the postage due. USPS tracking says they're not accepting the package for shipment. ?I've had this happen a few times. When it's from an individual, and just a bit short, I get a note in my mailbox to come and pay. ?The Chinese packages are a different story.?
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It's not one of those phishing emails or texts. I get those almost everyday too. The ones that tell me that some package I supposedly ordered is in customs or some warehouse, and I'm supposed to click a link to get it. This is the real USPS tracking from the real USPS tracking site, and the local mail folks.?
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Let's hope the rather passive-aggressive bot I chatted with is as helpful. ?I'm supposed to hear from them in a few days. ?According to the tracking, it's been in Chicago since Sept. 27.?
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Still sounds scammy to me.?
Mike Davis WA1MAD
(h) 781 545-4381
(c) 617 909-5103
On 10/11/2024 4:43 PM CDT James Todd <toddjam@...> wrote:
?
?
It's not one of those phishing emails or texts. I get those almost everyday too. The ones that tell me that some package I supposedly ordered is in customs or some warehouse, and I'm supposed to click a link to get it. This is the real USPS tracking from the real USPS tracking site, and the local mail folks.?
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Well, I'm also not 100% confident the diodes are real. ?I'll update if I ever get them. ?
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Pietro Molina
Michael Davis
Kevin - K5KTM