Total posts : 45366
It is interesting isn’t it regarding the range of the Ramsey vs say a C-Crane or Decade…not to mention the avg TPO on them.
On the 100 model, which is what I use, its peak output once the two filters are tuned properly is roughly 28mW. If the last filter is bypassed, which really does nothing in the way of filtering when in place, the output will jump to around 62mW. Obviously the 2nd filter serves more as an attenuator, though the circuit is indeed a filter. The majority of filtering takes place at the bandpass torroid coil and two 4 turn coils prior to it and both before the final output transistor.
Combined with both filters and the use of the internal whip, the field strength @ 3m comes in at around 360uV..plus or minus a few points depending on nearby objects absorbing the signal. These are not accurate, just ball park measurements using a quick and dirty altered 75-300 ohm adapter with the coil removed so the two “rabbit ear” whips are actually connected to the center conductor and ground of the analyzer connector.
From what I gather, the 100B model has a bit more output with the use of the FET element instead of a transistor. Much of the circuitry on the 100B is surface mount, whereas the 100 has the traditional feed through components and IC’s in sockets. The 100B has foil trace coils where the 100 has traditional wound coils.
However that 100B is also subject to the slightest static buildup and is prone to blow the output FET. My 100 model has been running 24/7/365 since the day I purchased it as a kit and its all pure stock with the exception of the PLL lock path using a different resistor to improve the bass response a bit in the audio…no other mods have ever been done to this unit.
I believe that if these were “too much little box”…right out of the box…that after 15 plus years and one model above the original, along with the 25 and 30 models, that the FCC and Ramsey would have done something by now to tone them down considerably.
Neither the FCC nor Ramsey has changed anything regarding these kits.
I attached my 100 model to an external 1/4 ground plane antenna through 25 feet of RG-59U coax with the antenna sitting on a fence pole about 10 feet in the air and the range is roughly a 2 block radius clean stereo. By the time I reached 3 blocks, the reception lost the stereo but the mono signal was still quite clear. At 4 blocks the mono signal began to fade in and out and at 5 blocks it dropped off sharply. With the internal whip, the range is about half, which is plenty IMO…but also not such a huge amount that would present problems in as far as the range they can cover.
The outdoor antenna is mounted so that there is nothing in the line of sight from it and going up the street 5 blocks to test the signal. Perhaps with another 10 feet of height on the antenna the range might improve a bit.
I saw a Ramsey unit being used in a photograph recently right here on this forum..I believe it was a radio swap meet or something featuring our SSTran maker holding a mic speaking into it while demonstrating the AMT5000…I could be wrong but that box sitting on top of the CD multi-changer sure looked like a Ramsey 100 or 100B box to me.
Point with that is are those Ramsey 100 and 100B models, or any other model with 25mW or so, that much of a concern when blatant pirate operations using several watts or far more give anyone concern in having a Ramsey or using one?
And there are thousands of them in use all over the country by now I would imagine.
It can be a bit scary eh. But as I have pointed out, as have many others across different forums including Ramsey’s own forum…if these things were that much of a problem, the FCC would have required Ramsey to do something about them a very long time ago. This also applies to their AM-25 unit and the “can operate at 1 watt” debate.
Out of them all…every single manual that comes with them do point out that it is up to the end user to operate them properly and use the supplied parts and antenna. Ramsey also has the operating information posted on their website and forum.
I prefer to use the Ramsey unit simply because it is in a metal cabinet, well grounded and shielded, uses a grounded AC plug unlike others that run via a wal wart adapter, and all the IC’s are field replaceable as they all sit in sockets…though I have yet to replace a single IC or other component due to failure. I have a Panaxis FM-10 transmitter fully equipped with the stereo generator, PLL exciter, 10 watt power amp and power supply all within the original rack mount cabinet. It sits in the “X” closet and has been there since the day I completed the Ramsey 100 assembly and began using the Ramsey.
I suppose its all a matter of personal preference using them or not. I truly believe that using any of those Ramsey units within their designed parameters that no one has anything to worry about..again since it has been 15 years these things have been on the market and continue to be marketed, that they are not of any major concern to the FCC with their 25mW of power.
An interesting point regarding the legality. An example is the Rangemaster and its power adjustment capability. Most declare that this is to compensate for antenna system loses. Well that is all well and good, and no big deal really. However in as far as legality to the letter of the law…well we all know the numbers don’t we. And no where in those rules does it say anything about a Part 15 certified unit being able to have the ability to power adjust to compensate for the set length limit of a 3 meter antenna system….yet that transmitter can have its power adjusted considerably, and even if it is to compensate for antenna system losses, that power adjustment anywhere above the 100mW limit takes the unit itself outside of that set limit, therefore it is no longer at the 100mW input power limit, but more and sometimes a lot more.
So what is the legality of that situation??? Just because the FCC went ahead and stamped a certification number on it…even when the test unit also had the power adjustment capability and known to the FCC…did the FCC stamp that certification number on it WITH having the unit tested at its full adjustment range for power???
I doubt it.
The Procaster…its power is pre-set to run between 95 and 105 mW, which self adjusts but does not go anywhere beyond 105 or so mW. A far cry from some who have measured the Rangemaster’s TPO of 400mW idle.
Which one is more “legal” or gives an operator more comfort in being in compliance???
Point here is that there are units with no certification number, put out a bit too much power and range yet continue to be manufactured and sold in the US, while others carry certification numbers and can be adjusted way beyond the legal limits.
So to be saying one is compliant when operating a unit that can be adjusted 300 percent above the legal limit regardless if its to compensate for losses or not, and one that operates with no power adjustment at 25mW and be so worried about compliance because there is no FCC number on it, yet continues to be marketed and sold…well one has to wonder if all of this is just bandy back and forth debate material for late night round table forum discussions instead of any real legal issue.
Its all interesting anyway. Whatever works for each individual. Live and let live is my motto.