Uniden President HR2510
The President HR2510 is an all mode 10 meter radio. It has AM, FM, LSB, USB and CW modes. 6 digit frequency display and built in SWR meter. An unlocked HR-2510 can have coverage from 24.800 - 29.999 MHz. It can transmit up to 30 watts and are tunable up to 40 watts.
Radio Shack produce a model called the HTX100 branded under Realistic trademark or the name Radio Shack. The HTX100 was a crippled version of the President HR2510. The Emperor TS-5010 is also comparable, and has the same output finals. The HR2510 and TS5010 transmit up to about 30 watts. The HR2510 included a full frequency compliment in the processor making it easy to open up for use on Citizen Band. Uniden discontinued the HR2510 under pressure from the FCC and released a crippled HR2600, a similarly featured radio, which no longer included the CB bands, but included some additional enhancements for 10 meter FM use.
With a General Class HAM radio license, using the HR2510 is both legal and productive for making long distance contacts on 10-meter with excellent signal reports. **
**This has been challenged. A transceiver that can transmit both on Citizen Band and Amateur Radio is not legal in the U.S. However it is a fact that the HR2510 is legal for amateur radio use as long as the radio has not been modified to operate out of band. Now since this was sold as a 10 meter radio you have to have it converted for it to work on the CB bands. There are a couple of different ways to do the modification and the results can vary - in some cases you may lose certain functions if you do the mod - or the freq will not display the correct channel - or in other cases you can add additional functions as is the case with the chipswitch modification. Once converted the HR2510 can have coverage from 24.800 - 29.999 MHz.
Due to the abuse of this radio, as in the illegal modifications allowing unlicensed individuals to operate on CB band, the FCC has deemed the President HR250 as "blacklisted." This may be referred to as having an unlocked clarifier. The FCC Market Blacklist due to CB Related Abuse does not make it illegal to own or buy this radio. It is illegal to market and advertise the product, so manufacture, import, and commercial sale of the President HR2510 was banned by the FCC. It is unfortunate as this truly is a 5-star 10-meter rig when used legally.
The President HR2510 was relatively inexpensive and could allow an entry level Tech class licensed HAM to make distant contacts on the HR band. In fact, a tech class is allowed CW, Data, and RTTY from 28.0 to 28.3Mhz. A Tech can also use SSB/CW from 28.3 to 28.5Mhz. This opens up an area of HF for the teach class for under $200.
LEGAL USE OF MODIFIED RADIO: It is true that in the event of a life threatening emergency, where all other forms of communication have been exhausted, you may operate out-of-band to find help. The FCC will forgive this out-of-band use in a life threatening emergency. Also, the disaster preparation community prefers to have these radios "unlocked" so the option is available in an emergency. An unlocked Uniden President HR2510 may still be legally operated within the correct band for a licensed operator, reserving the use of out-of-band frequencies for an extreme emergency situation. That's why it is nice to have it unlocked, even though it should not be used out-of-band.
RF Power output: AM/FM/CW: 10 W and SSB: 25 W
Deadkey on these radios from the factory was around 8-10 watts and should not be set any higher.
Standard features included Volume, Squelch, R.F. Gain, and a receive-only RIT control. Other features included a P.A. function, a switchable roger beep, a two position Mike Gain switch, and an effective Noise Blanker. The 10 segment LCD bar graph meter included S/R.F. and SWR functionality.
The frequency plan for the CB band, as well as the upper and lower portions of the "freeband", is included in the factory microprocessor's tuning tables, which only required a simple modification to enable.
The nomenclature is said to be something like this: the HR stands for Ham Radio, the 25 is for 25W PEP which is the output power, and the 10 because it's a 10m radio. This is not a confirmed or published fact, merely what has been stated by operators and is widely believed.
Factory frequency coverage: 28-29.7 MHz
Modified frequency coverage: 26-29.999 MHz
Bands: band selector switch after modification
A. 28.000 - 28.490 B. 28.500 - 28.990 C. 29.000 - 29.490 D. 29.500 - 29.690 E. 26.000 - 26.490 F. 26.500 - 26.990 G. 26.965 - 27.405 H. 27.000 - 27.490 I. 27.500 - 27.990
- Mode Selector - Selects CW, AM, FM, USB, or LSB.
- SWR CAL - Adjust the calibration of the SWR meter wile in the SWR CAL mode.
- RIT Control - The Receiver Incremental Tuning control match your xmit freq with rec freq. Very sensitive.
- RF Gain Control. - Varies the RF input to the receiver and helps eliminate strong, adjacent signals.
- Mic Gain. - Selects a lower Mic gain level. More gain is preferable unless distortion occurs.
- TX Switch - Locks the transmitter in the on position. This should be glued so it cannot be pressed.
- Meter Switch - Selects either RF/S, MOD, SWR CAL, or SWR.
- PA Switch - Selects the PA Mode if an external PA speaker is connected. Useless.
- NB Switch - Helps eliminate interference generated by vehicle ignition systems.
- Dim Switch - Selects the level of the backlight of the display.
- Scan Control - Used to scan up to 50 channels in each band segment.
- Span Control - Select 10 KHz, 1 KHz, or 100 Hz steps for the VFO.
- Channel UP/DOWN- Step up or down to the next 10 KHz channel in the currently selected band segment.
- Roger Beep- beep tone when you release the PTT switch. Should never be used, HAM ops dislike.
- Band Control - Selects one of four bands.
- F. Lock - Disables all frequency controls [except RIT] to prevent accidental changes of frequency.
- VFO Control - Digital Variable Frequency Oscillator control used to select the desired frequency.
- Squelch - Squelch weak and unwanted signal noise.
- Volume Control - Turns the unit on or off and adjusts the volume.
There are many mods available for this radio. However, some of the power output claims are false. One common completely false claim was that the pre-driver and final could be modified to get 90 Watts PEP output from the President HR-2510. This resulted in high sales of Motorola transistors necessary for the mod. In reality you can achieve an average increase of 15 Watts PEP or less than a 50% increase in output power. This increase amounts to approximately 1.5 dB or 1/2 of an “S” unit. The caution is that this might be at the expense of worse harmonics.
Repeater Split Mod
Avoid this mod. The use of switching diodes across the IF crystal filter in this mod will make it transmit dirty and destroy the diodes. Use a chipswitch
service and repair
The original transmit final transistor, the MRF 477 has been discontinued, and supplies have all but dried up. If you run out of spares, you are basically left with few options. It is possible to adapt a Japanese replacement transistor, but power output will likely be less. You can also retrofit the beefier MRF-450, 455 or similar stud mount "pill" type transistors. Power output will still not be as good as the original, but it will be a more reliable device.