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Re: Two feedlines on one band
Mike Olbrisch
THIS - would be an application where I'd start by installing the TCXO-9. And not the cheap-ass Chinese copy, the real Yaesu device. Most people don't really need the TCXO-9 at all. Even SSB on 70cm isn't too bad! But when you start messing with hi-tech stuff,.....
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Vy73 - Mike - KD5KC. El Paso, Texas - DM61rt. SOTA W5T-Texas Association Manager. NA-SOTA info is at: -----Original Message-----
From: FT817@... <FT817@...> Sent: Thursday, May 16, 2019 19:08 PM To: FT817@... Subject: [FT817] Re: Two feedlines on one band All that can be done with appropriate relays and logic. Ideally you would not drive the antenna and power amp relays from the ft817 as by the time the 817 goes to transmit, it is already producing RF which means you might narrowly avoid frying your preamp, or may not. The preamp relay should be sequenced first, then the power amp, then the driver. The 817 would ideally be locked to a stable reference, either rubidium or GPS sourced, as its drift on 432 is too much for digital modes. You may need to use both VFOs unless you and your contacts can maintain constant frequency on the moon, otherwise you need to tx and rx on different frequencies due to doppler shift which is significant - out of RIT range IIRC. The moon-net mailing list is a source of many ideas and answers. Find it via PE1RKI. 73 Andrew VK1DA/VK2UH ------------------------------------ Posted by: andrew73@... ------------------------------------ And for a great FAQ ( Frequently Asked Questions ) see Some really good technical info at: . Please note that your messages and files sent to this group may appear anywhere on the Internet or in print without notice or compensation. ------------------------------------ Yahoo Groups Links |
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Re: Two feedlines on one band
All that can be done with appropriate relays and logic. Ideally you would not drive the antenna and power amp relays from the ft817 as by the time the 817 goes to transmit, it is already producing RF which means you might narrowly avoid frying your preamp, or may not. The preamp relay should be sequenced first, then the power amp, then the driver.
The 817 would ideally be locked to a stable reference, either rubidium or GPS sourced, as its drift on 432 is too much for digital modes. You may need to use both VFOs unless you and your contacts can maintain constant frequency on the moon, otherwise you need to tx and rx on different frequencies due to doppler shift which is significant - out of RIT range IIRC. The moon-net mailing list is a source of many ideas and answers. Find it via PE1RKI. 73 Andrew VK1DA/VK2UH |
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Re: re external battery for ft 818 nd
Dan,??
You didn't pay attention. The pack is 11AH and the full charge voltage is 12.6, the cutoff (for battery safety)? voltage is about 9V.? This gives the best run time for about 85% of the battery? capacity.? That is enforced by the BMB (battery management board) built into? the pack. That pack is 11oz. Generally with NIMH cells in the radio its fairly heavy and adding 11oz more? for?the 11ah pack?is not at all bad.? Its only a consideration for moving about? in the field.??For remote but not on the move like field day a 33AH lead AGM? (or two)?is the trick. FYI: the typical Lipo cell is 4.2V full charge but average discharge voltage is about? 3.7V so a 3S pack averages about 11.1V and is ideal for full 5W operation of the? FT817.? At less than about 11V the power amp (SSB) gets unhappy and starts? clipping unless backed down (lower mic gain or 2.5W setting).? ?So based on? battery capability its a good match and far lighter than a 7Ah gell cell? (about 1/3 the weight).?? ? s a good source of data and testing. Allison |
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Re: re external battery for ft 818 nd
kc3vobob,
I am both aware and use battery management board and battery monitor boards. I've been at this a very long time. Its one of the rare times talking/writing about Lithium battery tech I left that? detail out.? ?If you are building series cell packs they are a MUST HAVE both? for?safety and best possible battery life.? Needless to say they must be matched? to the battery (number of cells and chemistry) in use.? Those board do multiple? things, they cut the pack off (open the circuit) if any cell is over voltage, under voltage, the applied charge voltage is excessive, and add over current? polyfuse?to protect against shorts. With due consideration and proper handling I've come to expect very? long battery?life and no exciting moments. Generally the most likely failures are the pouch cells used for model? cars?and planes?as they are fully unprotected and can be mechanically? damaged.? I do not use these as they rarely would fit my needs. I've only seen "energetic failures" in the hands of others that didn't take? due care.? Usually after telling them DO NOT DO THAT! Allison |
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Re: Two feedlines on one band
开云体育I’m pretty sure the antenna port is separate by VFO, and I think it’s also stored in memories.?Dan -- . Please pardon any mispelings or errors. On May 15, 2019, at 4:37 AM, 'Mike Olbrisch' Mike-2020@... [FT817] <FT817@...> wrote:
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Re: Two feedlines on one band
Mike Olbrisch
I think the antenna jack is set by band, not separately by VFO. Try it. What you can do is keep that selected in the menu and manually switch over when needed. Using JT65, you have about two seconds at the end of each transmission or reception period.
Many folks operate satellite using TWO FT-817s, one for TX and one for RX. If you only have one, that will not fork for you. But it might be a good excuse to get another. Perhaps you can find one with a bad TX or bad RX for cheap. OR – if you are running under computer control, perhaps even one with a bad display that someone is not using anymore. Good luck. Do share what you learn. Vy73 - Mike - KD5KC. El Paso, Texas - DM61rt. SOTA W5T-Texas Association Manager. NA-SOTA info is at: <> From: FT817@... <FT817@...> Sent: Tuesday, May 14, 2019 12:25 PM To: FT817@... Subject: [FT817] Two feedlines on one band Hi all, New to the group; thanks for having me. I'm wondering if there's any way to use separate transmit and receive feedlines on my 818, so that I can implement an LNA using one SPDT relay; I'm working EME on 432 with JT65. Maybe a command to set VFOa to one antenna port and VFOb to the other while using split mode? Thanks and 73, Chris K2QFA [Non-text portions of this message have been removed] |
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Re: re external battery for ft 818 nd
开云体育12v is overkill because the radio is quite happy on less—the rest is just converted to heat. If I don’t have to carry the weight, so much the better.?Dan -- . Please pardon any mispelings or errors. On May 14, 2019, at 9:48 AM, kb1gmx@... [FT817] <FT817@...> wrote:
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Two feedlines on one band
Hi all, New to the group; thanks for having me. I'm wondering if there's any way to use separate transmit and receive feedlines on my 818, so that I can implement an LNA using one SPDT relay; I'm working EME on 432 with JT65. Maybe a command to set VFOa to one antenna port and VFOb to the other while using split mode? Thanks and 73, Chris K2QFA |
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Re: re external battery for ft 818 nd
开云体育BEWARE of "cell imbalance" with any lithium battery using series connected cells! If circuitry to maintain balance is not present, the voltage division among cells may drift out of tolerance during charging or usage. Such imbalance can result in dangerous overcharge, during charge, or a cell deeply discharging, during use! Periodically measuring individual cell sections is a good idea, and problems should be corrected, by individual charge, discharge, or replacement. (2 series cells, charged by 8.4 volts, could be 4.2 volts each, (ideal situation) OR they could be 3.2 volts and 5.2 volts, potentially a dangerous situation! (Just as a discharge scenario of 2 cells, one at 2.5 volts and the other at 3.6 volts-total is 6.1 volts looks OK, but lower voltage cell will get damaged, especially if high current is drawn!)-73, KC3VO, Bob. On May 14, 2019, at 12:00 PM, kb1gmx@... [FT817] <FT817@...> wrote:
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Re: re external battery for ft 818 nd
so a 3S pack is 12.6 full and 8.7V at cutoff.? My 11ah 3S4P pack using LG? 2800mah 18650 LiPo give a very good run time. I'd prefer LiFePo as they are less fussy and more stable but I've never had? had issues with LiPo 18650 cells though I admit I am careful to use the? correct charger and and never charge faster than 3 hour rate for them. I may add I have some very old cells (over 15 years) that came from retired? Laptops that I still use as its a good tech if not improperly handled. Allison |
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Re: re external battery for ft 818 nd
>> LiFePo4 battery BUT it is 12 volt 12 amp hr.<<<
How is that overkill?? 12V is good and 12AH is a lot of power but if you running it for more? than 10 hours that's the battery to have. I use a 11AH pack for runing the 817 I have as that give me at least 10 ours often more depending on the ratio of RX to TX. Allison |
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Re: re external battery for ft 818 ND
开云体育Have to agree with Ken. ?That sounds like another vendor. ? I have tested several Bioenno packs and they deliver exact what is advertised with some fade margins. ? Other vendors I tested advertised 24AH lead acid equivalent and they delivered about 2AH. ? Dave VE7HR? On May 14, 2019, at 9:29 AM, Ken Hansen ken@... [FT817] <FT817@...> wrote:
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Re: re external battery for ft 818 ND
"Wonky specs" are not something I've noticed with Bioenno LiFePo4 battery packs, could you cite some specific examples?
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In my experience bioenno batteries are properly labeled and from all accounts well-regarded by owners. I am certain that if Bioenno tried to play such games with their power ratings the largest ham retailers would drop them like a hot potato. It would be the rare ham that would spend $100 on an 8 amp battery pack and be satisfied with a 2 amp pack at the quoted/needed 12 volt level. Are you perhaps thinking of another battery vendor? Ken, N2VIP On May 14, 2019, at 7:36 AM, 'Mike Olbrisch' Mike-2020@... [FT817] <FT817@...> wrote: |
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Re: re external battery for ft 818 ND
Mike Olbrisch
You have to be careful with the bioeny packs. Some of them post their specs wonky. Many of them count the max voltage as series cells, but list the available current as parallel cells. So if it says 12volts max voltage and 8 amps max current, when you look inside it is 4 cells. In series they are 12v @ 2A, and in parallel they are 3v @ 8A. Get the picture?
The very best battery packs I ever found for the FT-817 are from Buddi-Pole. They are built for quality. They are safety-protected for over current and heat, they have a very thick output cable with Anderson Power Poles already installed, and they are double-wrapped in heavy black heat-shrink. Not cheap, but I think worth it if you go to the field a lot. Vy73 - Mike - KD5KC. El Paso, Texas - DM61rt. SOTA W5T-Texas Association Manager. NA-SOTA info is at: <> From: FT817@... <FT817@...> Sent: Tuesday, May 14, 2019 6:00 AM To: FT817@... Subject: Re: [FT817] re external battery for ft 818 nd Thanks all for the info. Didn’t even occur to me to look at the RC shops. That bioenno pack is definitely overkill. I’ll see what I can find in the next few weeks. Thanks, Dan -- Sent from my iPhone. Please pardon any mispelings or errors. On May 14, 2019, at 2:04 AM, 'Matt' doormatt@... <mailto:doormatt@...> [FT817] <FT817@... <mailto:FT817@...> > wrote: Hi Dan, they will be using a nominal voltage when calling it a 12V battery. In reality it would be fine for use with the 817/818 radio, but as Mike pointed out, the 3S LiFePO4 batteries are probably the best suited for use with these radios. RC model shops are a great source for these batteries, chargers and associated gear – I use hobbyking for my source of this type of thing and as they have warehouses across the world (including the US), you can find the same items in most of them. Pricewise I find that hobbyking are better than sources like you have linked to – and you are not stuck with single use chargers. As an aside, the associated charger for the linked battery would be fine for use overseas as long as you had an appropriate adapter to plug it in). One other comment, travelling on aircraft you need to be a little careful with batteries – as a general rule of thumb you can take sub 100WH lithium batteries in carry on luggage (but NOT checked luggage) without seeking approval from the airline, although some can be a little over assertive in how they apply rules, so best to check with them (and carry a printed out copy of the correspondence and any other paperwork that will smooth things through the airline security for you). Matt VK1MA From: FT817@... <mailto:FT817@...> <FT817@... <mailto:FT817@...> > Sent: Tuesday, 14 May 2019 2:19 AM To: FT817@... <mailto:FT817@...> Subject: Re: [FT817] re external battery for ft 818 nd Interesting. I didn’t realize that. This was the bioenno battery I was looking at: It lists as a 12V battery, then they also have the equivalent Ah listed as a 9V, but it’s corresponding charger isn’t international capable. Do you know of a US source for accucell? Thanks, Dan -- Sent from my iPhone. Please pardon any mispelings or errors. On May 13, 2019, at 7:41 AM, 'Matt' doormatt@... <mailto:[email protected]> <mailto:doormatt@...> [FT817] <FT817@... <mailto:FT817@...> <mailto:FT817@...> > wrote: No, not 3V – try 3.6V per cell, so the 3S LiFePO4 when fully charged should be 10.8V. A LiPo is 4.2V per cell – so a 4S LiPo is 16.8V – outside the safe voltage range for pretty much any radio designed for a nominal 12V system. Personally I use 3S LiPo batteries for my 817 (and 4S LiFePO4 for the radios that need to be around 13.8V) I use a turnigy accucell 6 (which runs off 12V DC) and a 12V 2.5A plug pack (aka wall wort?) to power the charger. My plug pack accepts 100-240V 50/60Hz input, so with the addition of an appropriate adapter can be used around the world to charge my batteries. Or you can power the charger direct with 12V DC from a car if you wish. The accucell6 is cable to charge multiple different battery chemistries and up to 6 cells. Matt VK1MA From: FT817@... <mailto:FT817@...> <mailto:FT817@...> <FT817@... <mailto:FT817@...> <mailto:FT817@...> > Sent: Monday, 13 May 2019 11:05 PM To: FT817@... <mailto:FT817@...> <mailto:FT817@...> Subject: Re: [FT817] re external battery for ft 818 nd A 3S is 9V, right? What do people use to charge it outside the US? I’ve got some international travel on the horizon, and want to take my radio. I think batteries with a charger would be more flexible than trying to find a dual voltage power supply. The only charger (I’ve been looking at bioenno) for the 3S is 110v. Thanks, Dan -- Sent from my iPhone. Please pardon any mispelings or errors. On May 13, 2019, at 6:21 AM, 'Mike Olbrisch' Mike-2020@... <mailto:Mike-2020@...> <mailto:Mike-2020@...> <mailto:Mike-2020@...> [FT817] <FT817@... <mailto:FT817@...> <mailto:FT817@...> <mailto:FT817@...> > wrote: Li-Fe-Po4 is a good choice for the FT-817. A 3S is matched to the radio nearly perfectly, but a 4S will work. Just be certain the highest voltage of any battery you use does not exceed 16 volts and you’ll be OK. Vy73 - Mike - KD5KC. El Paso, Texas - DM61rt. SOTA W5T-Texas Association Manager. NA-SOTA info is at: <> From: FT817@... <mailto:FT817@...> <mailto:FT817@...> <mailto:[email protected] <mailto:FT817@...> > <[email protected] <mailto:FT817@...> <mailto:FT817@...> <mailto:FT817@...> > Sent: Sunday, May 12, 2019 17:21 PM To: FT817@... <mailto:FT817@...> <mailto:FT817@...> <mailto:FT817@...> Subject: [FT817] re external battery for ft 818 nd Newbie question here: Just got a ft 818 nd and I already have a LiFePo4 battery BUT it is 12 volt 12 amp hr. can I safely us this to power the radio? I know it is overkill for the Yaesu but since I already have the battery...I'd appreciate your advice! Thanks & 73's Dante WA2GVA [Non-text portions of this message have been removed] [Non-text portions of this message have been removed] [Non-text portions of this message have been removed] |
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Re: re external battery for ft 818 nd
开云体育Thanks all for the info. Didn’t even occur to me to look at the RC shops. That bioenno pack is definitely overkill. I’ll see what I can find in the next few weeks.?Thanks, Dan -- . Please pardon any mispelings or errors. On May 14, 2019, at 2:04 AM, 'Matt' doormatt@... [FT817] <FT817@...> wrote:
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