Beyond throttle and steering the 4 extra channels will allow user to run practically any auxiliary item with mixers also available for crawler steering and the like. Promo khusus pengguna baru di aplikasi Tokopedia! The Best RC Transmitters You Can Buy Today Futaba 3PRKA 3 channel 2.4G Flysky FS-GT3B Digital 3CH 2.4 GHz LCD Transmitter Radiolink RC4GS V2 2.4G RC Transmitter Included R6FG 6CH Gyro Receiver The Best RC Transmitters You Can Buy Today RC transmitters are the most important piece of equipment in your RC racing hobby. Log in to My Spektrum Get easy, online access to your Spektrum software updates, product registration and personalized settings. The receiver R6FG has been upgraded with the industrial 32bits M0 chip, all channels respond simultaneously within 12ms and ensure outstanding performance. Learn more In stock HobbyKing HK-GT2B 3CH 2.4GHz Transmitter and Receiver w/Rechargeable Li-ion Battery . Its model memory is as high as 250 and should be sufficient for rookies. (1) 3. Features 3 stabilization modes controlled by the "mode" switch on the transmitter. Get the DumboRC X6 Transmitter+Receiver here: https://amzn.to/3ncmcHyDumboRC X6 Transmitter and X6F/X6FG Receiver Unboxing -for RC Car, Truck, Boat. 3CH remote control for RC cars and boats. 10 Best rc vehicles radio transmitter receiver sets in Reviews 1. Compare. Radiolink RC4GS V2 Transmitter Dan Receiver R6FG / R7FG Dengan Gyro di Tokopedia Promo Pengguna Baru Cicilan 0% Kurir Instan. . Spektrum DX3S. The Spektrum DX6e is our top pick for the best RC transmitter for beginners. The easy setting ensures better control of gyro stabilization. Volantex RC 4CH Transmitter EAT403 for RC PLANE Decathlon 765-1, Super Cup 765-2, Mustang 768-1, Firstar 767-1. Radiolink RC4GS V3 5 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller 30 Models Strorage for Crawler, Buggy, Car, Boat View on Amazon SCORE 9.2 AI Score AI Score is a ranking system developed by our team of experts. Traxxas TQ 2.4 with Link. Transmitter is easily updated with the latest firmware. In an RC helicopter, both must be controlled. 1. In order to use this kind of radio with an RC helicopter, both the . Full gyro control via remote and a very easy to navigate GUI. KO Propo KO-92395. 6-Channel 2.4GHz FHSS and telemetry capable radio system. Mixed mode remote controller can be used with cars, boats, and tanks 3. Mobile Phone Accessories . Default transmitter stick inversion and possible gyro defect: StandardNoble: Scratchbuilt Multirotor Drones: 1: Apr 16, 2016 11:08 PM: Discussion: Plane gyro/receiver/servo connector questions: smellofhot: Beginner Training Area . 8 . RadioLink 2.4GHz 6 Channel RC6GS Radio Transmitter with R6FG Gyro Receiver #RC6GS $89.00 $79.99 Compare Add To Cart RadioLink RC4GS V3 2.4G 4CH Car Controller Transmitter + 6CH R6FG Gyro Inside Receiver for RC Car Boat (400m Distance) $49.99 Compare Add To Cart Radiolink T8FB Transmitter & R8EF Receiver 2.4GHz 8CH Transmitter & Receiver & OTG line Radios & Receiver; Multi Rotor Parts; FPV System; RC Quadcopter Parts; SEE MORE. steering causes failsafe/low voltage mode. Radiolink RC6GS V3 7Channels RC Transmitter and Receiver R7FG 2.4g Gyro RSSI. RadioLink Rc6gs 2.4g 6ch RC Transmitter Controller R7fg Receiver for RC Car Boat. FLYSKY . Beli Radiolink RC4GS V2 Transmitter Dan Receiver R6FG / R7FG Dengan Gyro di END.ID. Jeti DS16G2 or DS24. Find the best RC radios and receivers with the latest functions and features from top brands including Turnigy, OrangeRX, FrSKY, RADIOMASTER, and more. Flysky Rc FS-GT5 is a 6 channel rc transmitter (and receiver) uses 2.4gHz reliable AFDHS2a protocol. DumboRC X6 2.4GHz 6CH FHSS Radio Transmitter Support Gyro Sensitivity Adjustment with X6FG RC Receiver for JJRC Q65 MN-90 RC Car Boat Tank Model Parts 2441 reviews COD FlySky Noble NB4 2.4GHz 4CH AFHDS 3 Radio Transmitter HVGA 3.5" TFT Colors Touch Screen with FGr4/FGr4S RC Receiver for RC Car Boat 549 reviews COD Fast response speed and strong anti-interference ability. It, hence the name, receives the signals created by the transmitter. No more lugging around a heavy transmitter holding 8 x AA batteries! 840 feet. Radiolink R7FG Gyro Receiver 7CH 2.4G Two-Way Transmission Telemetry Long Range FPV Car Boat Receiver for RC Transmitter RC6GS RC4GS T8S T8FB Radio Controller System. The more I read about them, the more I think that the "rescue" mode won't help me . An RC helicopter radio is different from an airplane radio in several ways. Once received, the receiver sends the communicated signals to various components. | Shopping New Zealand. Radiolink RC6GS V2 6 Channels RC Transmitter and Gyro Receiver R7FG, Voltage Telemetry & Long Range Control, 2.4Ghz Surface Radio Controller for RC Crawler, Drifting, Buggy Cars and Boats View on Amazon SCORE 9.4 LR Score LR Score is a ranking system developed by our team of experts. X9 2.4GHz 9-Channel FHSS Radio Transmitter w/ RG206S RC Receiver USD 139.00 USD 159.77 Add to Cart KO Propo KO-80717 MC-8 2.4GHz MX-F MAKE-B 8-Channel Radio MD-2 Twin Motor Mixing ESC Set USD 84.00 Add to Cart KO Propo KO-80718 MC-8 2.4GHz MX-F MAKE-C 8-Channel Radio ESC Special Set USD 109.90 Add to Cart Hiro Seiko HS-48692 Volantex RC Transmitter 4 Channel EAT402 fit for 76101; 76102; 76103; 76104. Radiolink RC4GS V3 5 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller 30 Models Strorage for Crawler, Buggy, Car, Boat 1,431 1 offer from $64.99 Radiolink RC6GS V3 7Channels RC Transmitter and Receiver R7FG 2.4g Gyro RSSI Voltage Telemetry & Long Range Radio Remote Controller for RC Crawler Cars Boats Buggy Tank Black It is anti-slip and keeps the uni-direction. Works between 2.400GHz to 2.4835GHz frequencies, divided into 160 wave bands. Radiolink RC4GS V3 5 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz,New. RC ELECTRONICS; Gyros / Flight Stabilizers; Announcement. . Transmitter is a Detrum Gavin 6A, 6 channel 2.4 ghz transmitter. It is anti-slip and keeps the uni-direction. GoolRC 2.4G 3CH AFHS Radio Remote Control Transmitter with Receiver for RC Car Boat Features : Lighting Price: 43.99 for, Until 7.183CH remote control for RC cars and boats. Make sure the receiver antenna on your RC is properly installed, not twisted or broken, not touching metal parts inside the RC, and not dragging on the ground. For beginners looking to master the art of using RC transmitters and receivers, this is a great option. 620 feet. RC transmitters and receivers are essential for all serious hobbyists. RC Parts. . $36.00. Matybobe RC Transmitter and Receiver 2.4GHz 3CH RC Controller Digital Radio Remote Control Transmitter with Receiver for RC Car Boat High receiving sensitivity. Taranis Radio Screen Icons. Similar to "SAFE". R7FG is a 7 channels receiver with gyro built-in, high voltage servo support, and model voltage telemetry support. We can connect them directly to the RAW pin of the Pro Mini which has a voltage regulator that reduced the voltage to 5V. Related Searches: Shipping to: Language: . USD 34.90. DOGOU RC4GS V2 RC Transmitter 4 Channels and Receiver R6FG with Gyro 400M Remote Controller for Car Boat Truck Eachine Spitfire 2.4GHz EPP 400mm Wingspan 6-Axis Gyro One-Key U-Turn Aerobatic Mini RC Airplane RTF for Trainer Beginner 212 reviews. 4 Stars, 0 product ratings 0. Gyro/Receiver/Dual Rate/Expo. 10 bids 10 bids 10 bids + $9.41 shipping + $9.41 shipping + $9.41 shipping. Traxxas Rustler VXL Brushless. FlySky Hobby RC Receivers & Transmitters Best Selling FLYSKY FS-BS6 6CH Fail-Safe Receiver with Gyro Stabilization System - Black (12) $21.42 New Flysky FS-GT2 Radio Model RC Transmitter with Receiver (2) $39.82 New FlySky FSIA6B Receiver IBUS Port (38) $14.00 New FlySky X96MINI Receiver & Transmitter Set - SAH2562056095289LO (1) $66.29 New RC6GS . Collapse. DUMBORC X4 4CH RC Radio System Transmitter and Receiver X6F 2.4ghz Remote Controller for RC Car Boat Tanks (Distance 400m-500m) Controller Transmitter. Receiver is a Detrum MSR66A, 6 channel sport receiver, Istone 2.4ghz. 58 Reviews. This item: Radiolink RC4GS V3 5 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller 30 Models Strorage for Crawler, Buggy, Car, Boat $64.99 In Stock. Forward Programming uses the existing bi-directional communication link between a transmitter and receiver to do the same sophisticated programming that once required a cable . New Detrum tech Gavin 8CH transmitter SR86A gyro receiver: Detrumtech: Radios: 9: Aug 07, 2021 06:03 PM: Help! The receiver operates on around 4.5-6.2v. Original Flysky FS-i6s 2.4G 10CH AFHDS 2A Touchscreen Transmitter with FS-iA6B 6CH Receiver for RC Airplane Helicopter Multicopter. Very low power consumption, and stable performance. Features : Excellent Anti-interference: With pseudo random FHSS algorithm, which makes RC4GS with excellent anti-interference ability, control range up to 1300 feet (400 meters). Aux1 is a 'panic button' which initiates a basic return to home (RTH) function using the models on board gyro and accelerometer to guide the model back towards the Tx. DUMBORC-X6 2.4Ghz 6 Channel RC Transmitter with Gyro Inside Receiver Low Power Alarm and Out of Control Protections Radio Controller for Remote Car /Boat/Tank Mixed Mode Remote Controller 1,421 3 offers from $39.25 Radiolink RC4GS V2 4 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller for Crawler, Truck, Car, Boat 58 Reviews. 2.4G technology, FHSS 67 channels frequency-hopping spread spectrum, highly resistant to anti-jamming. With the transmitter chip of STM32F103RB and the receiver chip as the industrial 32bits ARM Cortex M0, RF chip is CC2500 from US, all channels of . Add To Cart. The signals between the receiver in the RC and the transmitter travel between the antennas. Radio controller has a gyro inside the receiver for better stability What sets this aparts is the premium features for the price - 20 model memory, full gyro control via remote and a very easy to navigate GUI. 5. Smooth and highly sensitive to control inputs and stable at distances from 400-500m. Buy On Amazon. 4. 1 Radiolink RC6GS V2 6 Channels RC Transmitter and Gyro Receiver R7FG, Voltage Telemetry & Long Range Control, 2.4Ghz Surface Radio Controller for RC Crawler, Drifting, Buggy Cars and Boats View on Amazon SCORE 9.4 LR Score LR Score is a ranking system developed by our team of experts. 7 channels dual antenna . Admiral RX600SP 6-Channel DSMX Compatible Receiver with Stability Plus Gyro [ADMR04] Motion RC Home Admiral RX600SP 6-Channel DSMX Compatible Receiver with Stability Plus Gyro SKU: ADMR04 Admiral RX600SP 6-Channel DSMX Compatible Receiver with Stability Plus Gyro $ 34 99 Buy in monthly payments with Affirm on orders over $50. However there is no antenna diversity and no telemetry. Standard receiver R6FG packed is the receiver with built-in gyro and supports high voltage servo. Radiolink RC4GS V3 5 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller 30 Models Strorage for Crawler, Buggy, Car, Boat Excellent Anti-interference: With pseudo random FHSS algorithm, which makes RC4GS V3 with excellent anti-interference ability, control range up to 1300 feet (400 meters). $89.00 $79.99. Tactic TTX-240. Traxxas tqi 2.4 ghz transmitter receiver. 2. $51.99 New. 6 watchers 6 watchers 6 watchers. CSM SL720 Interface Program Install Help! Free Shipping (7) View details >> Quick view. Low power alarm and out of control protections protect your aircraft 2. FGr8B PWM PPM i-bus 8-Channel Receiver For AFHDS3 Transmitter. Find many great new & used options and get the best deals for Radiolink RC6GS V2 6 Channels RC Transmitter & Gyro Receiver Used at the best online prices at eBay! $78.95 . The Eachine Minicube Flysky RX is a great option for outdoor models between 100mm and 180mm due to its 20x20mm mounting pattern, and pre-installed buzzer. Features : Used For :DUMBORC X6 Transmitter perfect used for RC Car Boat Tank model,2.4GHz Frequency and 3ms Receiver responses.Stable control your model 400-500M, make good works and protect when it out of control Low Power Alarm / Three Power Charging Modes of Remote Controller : This is a good fuctions for buyers when the transmitter lower powerlow voltage warning: 7.4V/4.8V,It can . The Minicube RX weighs 3.1g including the buzzer, but it is the most expensive RX here at just over $15. The included receiver is the X6FG and as mentioned includes a gyro on board. 4 channels mini receivers R4FGM/R4F designed for Mini RC cars. Item:RM9699. RadioLink Rc4g 2.4ghz 4-channel Digital Surface Radio W/ Gyro RC Car Boat Truck. Best Selling RC Transmitter & Receiver Overall Rating; DUMBORC X4 4CH RC Radio System Transmitter and Receiver: 9.8/10: Flysky FS-i6X 6-10(Default 6)CH 2.4GHz AFHDS RC Transmitter w/ FS-iA6B Receiver: 9.7/10: Radiolink RC4GS V2 4 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller: 9.6/10 Turnigy RC Transmitters and Receivers | Huge Selection | Best Value . Gyro Sensitivity Settings. I've looked at them all, and these 2 are the best. DUMBORC-X6 2.4Ghz 6 Channel RC Transmitter with Gyro Inside Receiver Key Features: 1. I think I have 4 Lemons altogether, 1 regular and 3 Stab+. . Flysky Remote Control 2.4G Flysky FS-A3 3 Channel Receiver Untuk RC . Standard receiver R6FG packed is a 6 channels receiver with built-in gyro and high voltage servo support. . DumboRC X6 2.4GHz 6CH Radio Transmitter with X6F RC Receiver for RC Vehicles Boat Tank Models without Gyro Function 306 reviews COD FlySky Noble NB4 2.4GHz 4CH AFHDS 3 Radio Transmitter HVGA 3.5" TFT Colors Touch Screen with FGr4/FGr4S RC Receiver for RC Car Boat 540 reviews COD Radiolink RC6GS V2 2.4 GHZ 6CH Transmitter and R7FG Receiver RC cars and boats. 808 feet. $67.19. I've got Lemon stabilizers in all my non-HH models. 5.0 average based on 2 product ratings. Turnigy GT5 6CH 2.4GHz AFHDS 2A Surface Radio w/GT5 Receiver (Gyro) SKU: 9114000081-0 . DumboRC X6 2.4GHz 6CH FHSS Radio Transmitter Support Gyro Sensitivity Adjustment with X6FG RC Receiver for JJRC Q65 MN-90 RC Car Boat Tank Model Parts 2440 reviews COD HBX 901A RTR 1/12 2.4G 4WD 50km/h Brushless RC Cars Fast Off-Road LED Light Truck Models Toys 50 reviews COD Features: Reliable, interference-free 2.4GHz AFHDS signal operation 3CH operation Rechargeable li-ion transmitter battery Interchangeable rubber hand grips Features : 1) 7 Channels: 2.4Ghz dual antennas with stronger signal, 1-6 channel output PWM signal, the 7th channel outputs SBUS/PPM signal. Radiolink RC6GS V3 7Channels RC Transmitter and Receiver R7FG 2.4g Gyro RSSI Voltage Telemetry & Long Range Radio Remote Controller for RC Crawler Cars Boats Buggy Tank Black 225 2 offers from $82.99 Product information Warranty & Support Product Warranty: For warranty information about this product, please click here Feedback Is the Flysky FS-GT5 6CH AFHDS RC Transmitter w/ FS-BS6 Receiver a reliable remote. 984 feet. MCD SC-330FET, 30A 4.8-24volt. Buy the best and latest rc transmitter and receiver on banggood.com offer the quality rc transmitter and receiver on sale with worldwide free shipping. The receiver has one or two gyro sensitivity pots depending on the model of the receiver to adjust the Elevator/Aileron sensitivity, changes the flight effect. $50.00 Used. Used 6 channel transmitter and receiver both in good condition. 05 of 09 2. Transceiver Range 433 mhz. SKU: 9114000042-0 . It has anti-interference compatibility, This is the reason that the performance is really smooth Gyro Receiver A built-in receiver made two-way communication possible. Hobbyking A-1 skyraider reciever connections. 3ms Response R6ds Receiver 2.4g RX 6ch PPM RadioLink Output SBUS PWM. INVENTO FS-R6B FS R6B 2.4G 6CH receiver For RC Transmitter FS CT6B 9ch TH9X TH9B. Volantex RC 4CH Transmitter EAT403 & EAR403 5CH Receiver with Gyro for RC PLANE Decathlon 765-1, Super Cup 765-2, Mustang 768-1, 767-2 $32.69 Volantex RC Ranger 600 RTF 761-2 RC Plane, W / 6-axis gyro stabilizer system and 2.4GHz 4-Channels Radio $98.00 Hobby Porter 4CH RC Car Receiver For 91803G-VT 2.4GHz 3CH Radio Remote Control Transmitter RC Car $24.99; Turbo Racing P32 91803G VT LCD Display SVC Gyro 2.4G 4CH Remote Control Transmitter RX41 Receiver RC $63.39; HOTRC DS-600 2.4GHz 6CH FHSS Built-in Lipo Battery Radio Transmitter with 4+2CH RC Receiver for RC $52.19 (1) $59.79 New. If you have a telescoping antenna on your transmitter, make sure it is fully extended. The X6. $78.95 . GoolRC TG3. Add to Cart. Adjust the pot (s) to make the helicopter more response or more stable. 6CH 2.4GHz RC Digital Transmitter with Gyro Receiver for 1/8 1/10 RC Car. The brain of this RC controller is an Arduino Pro Mini which is powered using 2 LiPo batteries producing around 7.4 volts. FS-GT5 Transmitter Receiver By Flysky for RC Car and Boat Product description and features Channel This is a 6 channel transmitter and receiver for the Rc cars and the boats. Free shipping for many products! Top Configuration. DumboRC X6A 2.4GHz 6CH Radio Transmitter Support Gyro Sensitivity Adjustment with X6FG Receiver for JJRC Q65 MN-90 RC Car Vehicles Model 205 reviews. I am keeping it under $70.00. Radiolink RC6GS V3 7 Channels 2.4Ghz RC Transmitter and Gyro Receiver R7FG, Voltage Telemetry, 30 Models Storage Surface Remote Radio Controller for RC Crawler, Drifting, Bash, Buggy Cars and Boats Visit the Radiolink Store 1,232 ratings | 213 answered questions -15% $8499 List Price: $99.99 & FREE Returns About this item Arduino RC Transmitter Circuit Diagram To begin with, let's take a look at the circuit diagram. You want a balance of good response and stability. The most important is the throttle for an RC airplane is used to control the engine speed, not the collective pitch. Compare. The Flysky FS-GT5 is a surface transmitter (and receiver) from Flysky suited for use in RC car and boats. Radiolink RC6GS V3 7Channels RC Transmitter and Receiver R7FG 2.4g Gyro RSSI Voltage Telemetry & Long Range Radio Remote Controller for RC Crawler Cars Boats Buggy Tank Black Features : 7-CHANNEL - CH3-CH7 can be customized to VR, three-way switch, and tact switch. The li-ion battery also makes this transmitter much lighter, which gives the user a great feel during use. 10. It from 0 to 10 are automatically scored by our AI tool based upon the data collected. Choose Options. 3. Smallest 6 Axis Gyro on the market (Approx 1 x 1 x .37 inches Weight of 2.83 grams) Uses Spektrum Forward Programing technology to program (Airware update needed) . Price is for both the transmitter and . RC6GS V2 is also compatible with the 4 channels mini receivers R4FGM / R4F designed for Mini RC cars, the 6 channels receivers R6FG / R6F , and the 8 channels long control distance receivers R8EF / R8F , which designed for RC boats. 5 Stars, 2 product ratings 2. 2 product ratings. RC Helicopter Transmitters Explained. 2.4G 4CH Remote Controller and Receiver: DUMBORC X4 Transmitter perfect used for RC Car Boat Tank Crawler,2.4GHz Frequency and 3ms Receiver responses. This item: WFLY ET08 8 Channels RC Transmitter and Receiver RF206S 2.4GHz Radio Remote Controller Airplane Voltage Monitor for RC FPV Racing Drone, Quad, Helicopter, Car,Boat (Mode 2 Left Hand Throttle) $66.88 Get it as soon as Wednesday, Jul 20 FREE Shipping on orders over $25 shipped by Amazon. These components are usually servos and / or an ESC. RadioLink RC4GS V3 2.4G 4CH Car Controller Transmitter + 6CH R6FG Gyro Inside Receiver for RC Car Boat (400m Distance) $49.99. With the integrated gyro in R7FG installed, vehicle turns more smoothly . $74.50 . Turnigy GT5 6CH 2.4GHz AFHDS 2A Surface Radio w/GT5 Receiver (Gyro) SKU: 9114000081-0 . Replacements are only around $10 and you can bind more than one to each transmitter although you will need to set up trims and dual rates each time you swap models if using more than one. 4. 3.3 out of 5 stars 15 . Radiolink RC4GS V2 4 Channels RC Transmitter and R6FG Gyro Receiver 2.4GHz Surface Remote Controller for Crawler, Truck, Car, Boat. However the 4 channel JFN transmitter also has two Aux buttons on the top which allow for additional functions. DUMBORC-X6 2.4Ghz 6 Channel RC Transmitter with Gyro Inside Receiver Low Power Alarm and Out of Control Protections Radio Controller for Remote Car /Boat/Tank Mixed Mode Remote Controller 1,508 $4299 Save 5% with coupon Get it as soon as Wed, Sep 14 FREE Shipping by Amazon More Buying Choices $41.08 (2 used & new offers) Ages: 14 years and up Standard receiver R7FG packed is the receiver with built-in gyro and supports high voltage servo. RadioLink 2.4GHz 6 Channel RC6GS Radio Transmitter with R6FG Gyro Receiver #RC6GS. Or is the Radiolink RC4GS V2 2.4G 4 Channels RC Transmitter and Receiver R6FG Gyro Radio Controller for Crawler Truck Car Boat a better remote? 5 Best RC Car Transmitter and Receiver : 1. The receiver is also known as the RX. It can be mounted in any orientation. Best budget receiver/gyro set up for Spektrum transmitter Apr 24, 2021, 10:29 PM. It covers the entire band width of the antenna bandwidth range. It is equipped with all the features that are essential for starters. With the integrated gyro in R6FG installed, the vehicle turns more smoothly, and drifting from high speed can be prevented. RadioLink RC4GS 2.4GHz 4CH Remote Control System Transmitter & R6FG Receiver with Gyro for RC Crawler Car Boat. No. Free shipping Free shipping Free shipping. Receiver response time is 3ms, ensuring a fast response and better control. With the transmitter chip of STM32F103RB, the operation speed of RC4GS is much faster than RC3S/RC4G with N572F072. It uses 2.4gHz digital transmission on the very reliable AFDHS2a protocol. US$69.99. 9CHP lcd screen replacement part.
Physical Therapy Masters Programs Near London, Head Graphene Xt Speed Mp 2022, Radial Master Cylinder Brembo, Animal-to Animal Organ Transplants, Startech Usb Ethernet Adapter Driver, Luxury Resorts Nevada Desert, Bontrager Race Bullhorn, 2022 Hyundai Tucson Limited Bose Sound System, Learning Internet Of Things Pdf,